diff --git a/src/main/java/umc/kkijuk/server/member/controller/EmailAuthController.java b/src/main/java/umc/kkijuk/server/member/controller/EmailAuthController.java
index 42e34761..304953e7 100644
--- a/src/main/java/umc/kkijuk/server/member/controller/EmailAuthController.java
+++ b/src/main/java/umc/kkijuk/server/member/controller/EmailAuthController.java
@@ -9,7 +9,7 @@
 import umc.kkijuk.server.member.emailauth.MailAddressDto;
 import umc.kkijuk.server.member.emailauth.MailCertificationDto;
 import umc.kkijuk.server.member.emailauth.MailCertificationResponse;
-import umc.kkijuk.server.member.emailauth.MailService;
+import umc.kkijuk.server.member.emailauth.MailServiceImpl;
 
 @Tag(name = "auth", description = "이메일 인증 API")
 @RestController
@@ -17,7 +17,7 @@
 @RequiredArgsConstructor
 public class EmailAuthController {
 
-    private final MailService mailService;
+    private final MailServiceImpl mailService;
 
     @Operation(
             summary = "이메일 인증번호 요청",
diff --git a/src/main/java/umc/kkijuk/server/member/controller/MemberController.java b/src/main/java/umc/kkijuk/server/member/controller/MemberController.java
index 30d42411..e6012cba 100644
--- a/src/main/java/umc/kkijuk/server/member/controller/MemberController.java
+++ b/src/main/java/umc/kkijuk/server/member/controller/MemberController.java
@@ -10,6 +10,7 @@
 import umc.kkijuk.server.member.controller.response.*;
 import umc.kkijuk.server.member.domain.Member;
 import umc.kkijuk.server.member.dto.*;
+import umc.kkijuk.server.member.emailauth.MailServiceImpl;
 import umc.kkijuk.server.member.service.MemberService;
 import lombok.RequiredArgsConstructor;
 
@@ -23,7 +24,7 @@
 public class MemberController {
 
     private final MemberService memberService;
-//    private final MailService mailService;
+    private final MailServiceImpl mailService;
     private int authRandomNumber; // 이메일 인증 숫자를 저장하는 변수
 
     @Operation(
@@ -43,7 +44,7 @@ public ResponseEntity<CreateMemberResponse> saveMember(@RequestBody @Valid Membe
             description = "회원가입시 이메일 중복을 확인합니다.")
     @PostMapping("/confirmEmail")
     public ResponseEntity<Boolean> confirmEmail(@RequestBody MemberEmailDto memberEmailDto){
-        Boolean result = memberService.confirmDupEmail(memberEmailDto);
+        Boolean result = mailService.confirmDupEmail(memberEmailDto);
         return ResponseEntity.ok(result);
     }
 
diff --git a/src/main/java/umc/kkijuk/server/member/emailauth/MailService.java b/src/main/java/umc/kkijuk/server/member/emailauth/MailService.java
index 440b5eee..053eae8d 100644
--- a/src/main/java/umc/kkijuk/server/member/emailauth/MailService.java
+++ b/src/main/java/umc/kkijuk/server/member/emailauth/MailService.java
@@ -1,78 +1,12 @@
 package umc.kkijuk.server.member.emailauth;
 
-import jakarta.mail.MessagingException;
-import jakarta.mail.internet.MimeMessage;
-import lombok.RequiredArgsConstructor;
-import org.springframework.beans.factory.annotation.Value;
-import org.springframework.mail.javamail.JavaMailSender;
-import org.springframework.stereotype.Service;
-import umc.kkijuk.server.common.domian.exception.CertificationNumberMismatchException;
-import umc.kkijuk.server.common.domian.exception.MemberAlreadyExistsException;
-import umc.kkijuk.server.member.repository.MemberJpaRepository;
+import umc.kkijuk.server.member.dto.MemberEmailDto;
 
-import java.util.Random;
+public interface MailService {
 
-@Service
-@RequiredArgsConstructor
-public class MailService {
+    MailCertificationResponse sendMail(String mail);
 
-    private final MailCertification mailCertification;
-    private final JavaMailSender javaMailSender;
-    private final MemberJpaRepository memberJpaRepository;
+    Boolean verifyMail(MailCertificationDto requestDto);
 
-    @Value("${spring.mail.username}")
-    private String senderEmail;
-
-
-    private String createRandomNumber() {
-        Random rand = new Random();
-        String randomNum = "";
-        for (int i = 0; i < 6; i++) {
-            String random = Integer.toString(rand.nextInt(10));
-            randomNum += random;
-        }
-
-        return randomNum;
-    }
-
-    public MailCertificationResponse sendMail(String mail) {
-        if(memberJpaRepository.findByEmail(mail).isPresent()){
-            throw new MemberAlreadyExistsException();
-        }
-
-        MimeMessage message = javaMailSender.createMimeMessage();
-        String randomNum = createRandomNumber();
-
-        try {
-            message.setFrom(senderEmail);
-            message.setRecipients(MimeMessage.RecipientType.TO, mail);
-            message.setSubject("이메일 인증");
-            String body = "";
-            body += "<h3>" + "요청하신 인증 번호입니다." + "</h3>";
-            body += "<h1>" + randomNum + "</h1>";
-            body += "<h3>" + "감사합니다." + "</h3>";
-            message.setText(body,"UTF-8", "html");
-        } catch (MessagingException e) {
-            e.printStackTrace();
-        }
-
-        javaMailSender.send(message);
-        mailCertification.createMailCertification(mail,randomNum);
-        return new MailCertificationResponse(mail, randomNum);
-    }
-
-    // 인증 번호 검증
-    public Boolean verifyMail(MailCertificationDto requestDto) {
-        if (isVerify(requestDto)) {
-            throw new CertificationNumberMismatchException();
-        }
-        mailCertification.deleteMailCertification(requestDto.getEmail());
-
-        return true;
-    }
-    private boolean isVerify(MailCertificationDto requestDto) {
-        return !(mailCertification.hasKey(requestDto.getEmail()) &&
-                mailCertification.getMailCertification(requestDto.getEmail())
-                        .equals(requestDto.getAuthNumber()));
-    }
-}
\ No newline at end of file
+    Boolean confirmDupEmail(MemberEmailDto memberEmailDto);
+}
diff --git a/src/main/java/umc/kkijuk/server/member/emailauth/MailServiceImpl.java b/src/main/java/umc/kkijuk/server/member/emailauth/MailServiceImpl.java
new file mode 100644
index 00000000..97ee81f3
--- /dev/null
+++ b/src/main/java/umc/kkijuk/server/member/emailauth/MailServiceImpl.java
@@ -0,0 +1,91 @@
+package umc.kkijuk.server.member.emailauth;
+
+import jakarta.mail.MessagingException;
+import jakarta.mail.internet.MimeMessage;
+import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.mail.javamail.JavaMailSender;
+import org.springframework.stereotype.Service;
+import umc.kkijuk.server.common.domian.exception.CertificationNumberMismatchException;
+import umc.kkijuk.server.common.domian.exception.MemberAlreadyExistsException;
+import umc.kkijuk.server.member.domain.Member;
+import umc.kkijuk.server.member.dto.MemberEmailDto;
+import umc.kkijuk.server.member.repository.MemberRepository;
+
+import java.util.Optional;
+import java.util.Random;
+
+@Service
+@RequiredArgsConstructor
+public class MailServiceImpl implements MailService{
+
+    private final MailCertification mailCertification;
+    private final JavaMailSender javaMailSender;
+    private final MemberRepository memberRepository;
+
+    @Value("${spring.mail.username}")
+    private String senderEmail;
+
+
+    private String createRandomNumber() {
+        Random rand = new Random();
+        String randomNum = "";
+        for (int i = 0; i < 6; i++) {
+            String random = Integer.toString(rand.nextInt(10));
+            randomNum += random;
+        }
+
+        return randomNum;
+    }
+
+    public MailCertificationResponse sendMail(String mail) {
+        if(memberRepository.findByEmail(mail).isPresent()){
+            throw new MemberAlreadyExistsException();
+        }
+
+        MimeMessage message = javaMailSender.createMimeMessage();
+        String randomNum = createRandomNumber();
+
+        try {
+            message.setFrom(senderEmail);
+            message.setRecipients(MimeMessage.RecipientType.TO, mail);
+            message.setSubject("이메일 인증");
+            String body = "";
+            body += "<h3>" + "요청하신 인증 번호입니다." + "</h3>";
+            body += "<h1>" + randomNum + "</h1>";
+            body += "<h3>" + "감사합니다." + "</h3>";
+            message.setText(body,"UTF-8", "html");
+        } catch (MessagingException e) {
+            e.printStackTrace();
+        }
+
+        javaMailSender.send(message);
+        mailCertification.createMailCertification(mail,randomNum);
+        return new MailCertificationResponse(mail, randomNum);
+    }
+
+    // 인증 번호 검증
+    public Boolean verifyMail(MailCertificationDto requestDto) {
+        if (isVerify(requestDto)) {
+            throw new CertificationNumberMismatchException();
+        }
+        mailCertification.deleteMailCertification(requestDto.getEmail());
+
+        return true;
+    }
+    private Boolean isVerify(MailCertificationDto requestDto) {
+        return !(mailCertification.hasKey(requestDto.getEmail()) &&
+                mailCertification.getMailCertification(requestDto.getEmail())
+                        .equals(requestDto.getAuthNumber()));
+    }
+
+    @Override
+    public Boolean confirmDupEmail(MemberEmailDto memberEmailDto) {
+        Optional<Member> member = memberRepository.findByEmail(memberEmailDto.getEmail());
+        if(member.isEmpty()){
+            return true;
+        }else{
+            return false;
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/umc/kkijuk/server/member/repository/MemberRepository.java b/src/main/java/umc/kkijuk/server/member/repository/MemberRepository.java
new file mode 100644
index 00000000..227f3b19
--- /dev/null
+++ b/src/main/java/umc/kkijuk/server/member/repository/MemberRepository.java
@@ -0,0 +1,11 @@
+package umc.kkijuk.server.member.repository;
+
+import umc.kkijuk.server.member.domain.Member;
+
+import java.util.Optional;
+
+public interface MemberRepository {
+    Optional<Member> findById(Long id);
+    Optional<Member> findByEmail(String email);
+    Member save(Member member);
+}
\ No newline at end of file
diff --git a/src/main/java/umc/kkijuk/server/member/repository/MemberRepositoryImpl.java b/src/main/java/umc/kkijuk/server/member/repository/MemberRepositoryImpl.java
new file mode 100644
index 00000000..73c3686d
--- /dev/null
+++ b/src/main/java/umc/kkijuk/server/member/repository/MemberRepositoryImpl.java
@@ -0,0 +1,28 @@
+package umc.kkijuk.server.member.repository;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Repository;
+import umc.kkijuk.server.member.domain.Member;
+
+import java.util.Optional;
+
+@Repository
+@RequiredArgsConstructor
+public class MemberRepositoryImpl implements MemberRepository{
+    private final MemberJpaRepository memberJpaRepository;
+
+    @Override
+    public Optional<Member> findById(Long id) {
+        return memberJpaRepository.findById(id);
+    }
+
+    @Override
+    public Optional<Member> findByEmail(String email) {
+        return memberJpaRepository.findByEmail(email);
+    }
+
+    @Override
+    public Member save(Member member) {
+        return memberJpaRepository.save(member);
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/umc/kkijuk/server/member/service/MemberService.java b/src/main/java/umc/kkijuk/server/member/service/MemberService.java
index fea7f270..ed41550d 100644
--- a/src/main/java/umc/kkijuk/server/member/service/MemberService.java
+++ b/src/main/java/umc/kkijuk/server/member/service/MemberService.java
@@ -19,7 +19,7 @@ public interface MemberService {
     Member changeMemberPassword(Long memberId, MemberPasswordChangeDto memberPasswordChangeDto);
     Member myPagePasswordAuth(Long memberId, MyPagePasswordAuthDto myPagePasswordAuthDto);
     MemberEmailResponse getMemberEmail(Long memberId);
-    EmailAuthResponse getEmailAuth(EmailAddressDto emailAddressDto, int number);
+//    EmailAuthResponse getEmailAuth(EmailAddressDto emailAddressDto, int number);
     MemberStateResponse changeMemberState(Long memberId);
-    Boolean confirmDupEmail(MemberEmailDto memberEmailDto);
+
 }
diff --git a/src/main/java/umc/kkijuk/server/member/service/MemberServiceImpl.java b/src/main/java/umc/kkijuk/server/member/service/MemberServiceImpl.java
index 925c9c75..3c5bab6f 100644
--- a/src/main/java/umc/kkijuk/server/member/service/MemberServiceImpl.java
+++ b/src/main/java/umc/kkijuk/server/member/service/MemberServiceImpl.java
@@ -13,6 +13,7 @@
 import umc.kkijuk.server.member.domain.State;
 import umc.kkijuk.server.member.dto.*;
 import umc.kkijuk.server.member.repository.MemberJpaRepository;
+import umc.kkijuk.server.member.repository.MemberRepository;
 
 import java.util.List;
 import java.util.Optional;
@@ -21,12 +22,12 @@
 @Transactional(readOnly = true)
 @RequiredArgsConstructor
 public class MemberServiceImpl implements MemberService {
-    private final MemberJpaRepository memberJpaRepository;
+    private final MemberRepository memberRepository;
     private final PasswordEncoder passwordEncoder;
 
     @Override
     public Member getById(Long memberId) {
-        return memberJpaRepository.findById(memberId)
+        return memberRepository.findById(memberId)
                 .orElseThrow(() -> new ResourceNotFoundException("Member", memberId));
     }
 
@@ -43,7 +44,7 @@ public Member join(MemberJoinDto memberJoinDto) {
         String encodedPassword = passwordEncoder.encode(memberJoinDto.getPassword());
         joinMember.changeMemberPassword(encodedPassword);
 
-        return memberJpaRepository.save(joinMember);
+        return memberRepository.save(joinMember);
     }
 
     @Override
@@ -85,7 +86,7 @@ public Member updateMemberField(Long memberId, MemberFieldDto memberFieldDto){
         if(!member.getField().equals(memberFieldDto.getField())){
             throw new FieldUpdateException();
         }
-        return memberJpaRepository.save(member);
+        return memberRepository.save(member);
     }
 
     @Override
@@ -96,7 +97,7 @@ public Member updateMemberInfo(Long memberId, MemberInfoChangeDto memberInfoChan
             throw new InvalidMemberDataException();
         }
         member.changeMemberInfo(memberInfoChangeDto.getPhoneNumber(), memberInfoChangeDto.getBirthDate(), memberInfoChangeDto.getMarketingAgree());
-        return memberJpaRepository.save(member);
+        return memberRepository.save(member);
     }
 
     @Override
@@ -113,7 +114,7 @@ public Member changeMemberPassword(Long memberId, MemberPasswordChangeDto member
         String encodedPassword = passwordEncoder.encode(memberPasswordChangeDto.getNewPassword());
         member.changeMemberPassword(encodedPassword);
 
-        return memberJpaRepository.save(member);
+        return memberRepository.save(member);
     }
 
     @Override
@@ -127,15 +128,6 @@ public Member myPagePasswordAuth(Long memberId, MyPagePasswordAuthDto myPagePass
         return member;
     }
 
-    @Override
-    @Transactional
-    public EmailAuthResponse getEmailAuth(EmailAddressDto emailAddressDto, int authRandomNumber){
-        return EmailAuthResponse.builder()
-                .email(emailAddressDto.getEmail())
-                .authNumber(authRandomNumber)
-                .build();
-    }
-
     @Override
     @Transactional
     public MemberStateResponse changeMemberState(Long memberId){
@@ -147,21 +139,22 @@ else if(member.getUserState().equals(State.ACTIVATE)){
             member.inactivate();
         }
 
-        memberJpaRepository.save(member);
+        memberRepository.save(member);
 
         return MemberStateResponse.builder()
                 .deleteDate(member.getDeleteDate())
                 .build();
     }
 
-    @Override
-    public Boolean confirmDupEmail(MemberEmailDto memberEmailDto) {
-        Optional<Member> member = memberJpaRepository.findByEmail(memberEmailDto.getEmail());
-        if(member.isEmpty()){
-            return true;
-        }else{
-            return false;
-        }
-    }
+//    @Override
+//    @Transactional
+//    public EmailAuthResponse getEmailAuth(EmailAddressDto emailAddressDto, int authRandomNumber){
+//        return EmailAuthResponse.builder()
+//                .email(emailAddressDto.getEmail())
+//                .authNumber(authRandomNumber)
+//                .build();
+//    }
+
+
 
 }
diff --git a/src/test/java/umc/kkijuk/server/member/mock/FakeMemberRepository.java b/src/test/java/umc/kkijuk/server/member/mock/FakeMemberRepository.java
new file mode 100644
index 00000000..438c5c8f
--- /dev/null
+++ b/src/test/java/umc/kkijuk/server/member/mock/FakeMemberRepository.java
@@ -0,0 +1,41 @@
+package umc.kkijuk.server.member.mock;
+
+import umc.kkijuk.server.member.domain.Member;
+import umc.kkijuk.server.member.repository.MemberRepository;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.concurrent.atomic.AtomicLong;
+
+public class FakeMemberRepository implements MemberRepository {
+    private final AtomicLong authGeneratedID = new AtomicLong(0);
+    private final List<Member> data = new ArrayList<Member>();
+
+    @Override
+    public Member save(Member member) {
+        if (member.getId() == null || member.getId() == 0){
+            data.add(member);
+            return member;
+        } else {
+            data.removeIf(item -> Objects.equals(item.getId(), member.getId()));
+            data.add(member);
+            return member;
+        }
+    }
+
+    @Override
+    public Optional<Member> findById(Long id) {
+        return data.stream()
+                .filter(item -> item.getId().equals(id))
+                .findAny();
+    }
+
+    @Override
+    public Optional<Member> findByEmail(String email) {
+        return data.stream()
+                .filter(item -> item.getEmail().equals(email))
+                .findAny();
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/umc/kkijuk/server/member/mock/FakePasswordEncoder.java b/src/test/java/umc/kkijuk/server/member/mock/FakePasswordEncoder.java
new file mode 100644
index 00000000..c8478aa5
--- /dev/null
+++ b/src/test/java/umc/kkijuk/server/member/mock/FakePasswordEncoder.java
@@ -0,0 +1,15 @@
+package umc.kkijuk.server.member.mock;
+
+import org.springframework.security.crypto.password.PasswordEncoder;
+
+public class FakePasswordEncoder implements PasswordEncoder {
+    @Override
+    public String encode(CharSequence rawPassword) {
+        return null;
+    }
+
+    @Override
+    public boolean matches(CharSequence rawPassword, String encodedPassword) {
+        return false;
+    }
+}
diff --git a/src/test/java/umc/kkijuk/server/member/service/MailServiceTest.java b/src/test/java/umc/kkijuk/server/member/service/MailServiceTest.java
new file mode 100644
index 00000000..c5ada5d1
--- /dev/null
+++ b/src/test/java/umc/kkijuk/server/member/service/MailServiceTest.java
@@ -0,0 +1,148 @@
+package umc.kkijuk.server.member.service;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import umc.kkijuk.server.common.domian.exception.CertificationNumberMismatchException;
+import umc.kkijuk.server.common.domian.exception.MemberAlreadyExistsException;
+import umc.kkijuk.server.member.domain.MarketingAgree;
+import umc.kkijuk.server.member.domain.Member;
+import umc.kkijuk.server.member.domain.State;
+import umc.kkijuk.server.member.dto.MemberEmailDto;
+import umc.kkijuk.server.member.emailauth.*;
+import umc.kkijuk.server.member.mock.FakeMemberRepository;
+import umc.kkijuk.server.member.mock.FakePasswordEncoder;
+import umc.kkijuk.server.member.repository.MemberRepository;
+
+import jakarta.mail.MessagingException;
+import jakarta.mail.internet.MimeMessage;
+import org.springframework.mail.javamail.JavaMailSender;
+
+import java.time.LocalDate;
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.*;
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.mockito.Mockito.*;
+
+public class MailServiceTest {
+
+    private MailService mailService;
+    private MailCertification mailCertification;
+    private JavaMailSender javaMailSender;
+    private MemberRepository memberRepository;
+
+    private final String testMemberEmail = "test@naver.com";
+
+    @BeforeEach
+    void init() {
+        mailCertification = mock(MailCertification.class);
+        javaMailSender = mock(JavaMailSender.class);
+        memberRepository = new FakeMemberRepository();
+
+        this.mailService = new MailServiceImpl(mailCertification, javaMailSender, memberRepository);
+
+        Member member = Member.builder()
+                .email(testMemberEmail)
+                .name("홍길동")
+                .phoneNumber("01012345678")
+                .birthDate(LocalDate.of(1999, 3, 31))
+                .password("testpassword")
+                .marketingAgree(MarketingAgree.BOTH)
+                .userState(State.ACTIVATE)
+                .field(List.of("game", "computer"))
+                .build();
+
+        memberRepository.save(member);
+    }
+
+    @Test
+    void sendMail_이미존재하는이메일_예외발생() {
+        // given
+        MemberEmailDto memberEmailDto = new MemberEmailDto(testMemberEmail);
+
+        // then
+        assertThatThrownBy(() -> mailService.sendMail(testMemberEmail))
+                .isInstanceOf(MemberAlreadyExistsException.class);
+    }
+
+    @Test
+    void sendMail_새로운이메일_메일발송성공() throws MessagingException {
+        // given
+        String newEmail = "newuser@example.com";
+        MimeMessage mimeMessage = mock(MimeMessage.class);
+        doReturn(mimeMessage).when(javaMailSender).createMimeMessage();
+
+        // when
+        MailCertificationResponse response = mailService.sendMail(newEmail);
+
+        // then
+        assertAll(
+                () -> assertThat(response.getEmail()).isEqualTo(newEmail),
+                () -> assertThat(response.getAuthNumber()).hasSize(6),
+                () -> verify(javaMailSender).send(mimeMessage),
+                () -> verify(mailCertification).createMailCertification(eq(newEmail), anyString())
+        );
+    }
+
+    @Test
+    void verifyMail_인증성공() {
+        // given
+        String authNumber = "123456";
+        MailCertificationDto requestDto = new MailCertificationDto(testMemberEmail, authNumber);
+
+        doReturn(true).when(mailCertification).hasKey(testMemberEmail);
+        doReturn(authNumber).when(mailCertification).getMailCertification(testMemberEmail);
+
+        // when
+        Boolean result = mailService.verifyMail(requestDto);
+
+        // then
+        assertAll(
+                () -> assertThat(result).isTrue(),
+                () -> verify(mailCertification).deleteMailCertification(testMemberEmail)
+        );
+    }
+
+    @Test
+    void verifyMail_인증번호불일치_예외발생() {
+        // given
+        String correctAuthNumber = "123456";
+        String incorrectAuthNumber = "654321";
+        MailCertificationDto requestDto = new MailCertificationDto(testMemberEmail, incorrectAuthNumber);
+
+        doReturn(true).when(mailCertification).hasKey(testMemberEmail);
+        doReturn(correctAuthNumber).when(mailCertification).getMailCertification(testMemberEmail);
+
+        // then
+        assertThatThrownBy(() -> mailService.verifyMail(requestDto))
+                .isInstanceOf(CertificationNumberMismatchException.class);
+
+        verify(mailCertification, never()).deleteMailCertification(testMemberEmail);
+    }
+
+    @Test
+    void confirmDupEmail_이메일중복확인_존재하는이메일() {
+        // given
+        MemberEmailDto memberEmailDto = new MemberEmailDto(testMemberEmail);
+
+        // when
+        Boolean isDup = mailService.confirmDupEmail(memberEmailDto);
+
+        // then
+        assertThat(isDup).isFalse(); // 이미 존재하므로 중복됨
+    }
+
+    @Test
+    void confirmDupEmail_이메일중복확인_없는이메일() {
+        // given
+        String newEmail = "newuser@example.com";
+        MemberEmailDto memberEmailDto = new MemberEmailDto(newEmail);
+
+        // when
+        Boolean isDup = mailService.confirmDupEmail(memberEmailDto);
+
+        // then
+        assertThat(isDup).isTrue(); // 존재하지 않으므로 중복 아님
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/umc/kkijuk/server/member/service/MemberServiceTest.java b/src/test/java/umc/kkijuk/server/member/service/MemberServiceTest.java
index f29f5801..6e046de2 100644
--- a/src/test/java/umc/kkijuk/server/member/service/MemberServiceTest.java
+++ b/src/test/java/umc/kkijuk/server/member/service/MemberServiceTest.java
@@ -2,214 +2,32 @@
 
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
-import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.boot.test.context.SpringBootTest;
-import org.springframework.boot.test.web.client.TestRestTemplate;
-import org.springframework.http.HttpEntity;
-import org.springframework.http.HttpMethod;
-import org.springframework.http.HttpStatus;
-import org.springframework.http.ResponseEntity;
-import org.springframework.test.annotation.DirtiesContext;
-import umc.kkijuk.server.member.controller.response.MemberFieldResponse;
-import umc.kkijuk.server.member.controller.response.MemberInfoResponse;
-import umc.kkijuk.server.common.domian.exception.ConfirmPasswordMismatchException;
-import umc.kkijuk.server.member.domain.MarketingAgree;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import umc.kkijuk.server.member.controller.response.EmailAuthResponse;
 import umc.kkijuk.server.member.domain.Member;
-import umc.kkijuk.server.member.domain.State;
-import umc.kkijuk.server.member.dto.MemberFieldDto;
-import umc.kkijuk.server.member.dto.MemberInfoChangeDto;
-import umc.kkijuk.server.member.dto.MemberJoinDto;
-import umc.kkijuk.server.member.repository.MemberJpaRepository;
+import umc.kkijuk.server.member.dto.*;
+import umc.kkijuk.server.member.emailauth.MailService;
+import umc.kkijuk.server.member.mock.FakeMemberRepository;
+import umc.kkijuk.server.member.repository.MemberRepository;
 
-import java.time.LocalDate;
-import java.util.List;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatThrownBy;
-import static org.junit.jupiter.api.Assertions.*;
-import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.mockito.Mockito.mock;
 
-@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
-public class MemberServiceTest {
 
-    @Autowired
-    MemberService memberService;
+class MemberServiceTest {
 
-    @Autowired
-    MemberJpaRepository memberJpaRepository;
-
-    @Autowired
-    private TestRestTemplate restTemplate;
+    private MemberService memberService;
+    private MemberRepository memberRepository;
+    private PasswordEncoder passwordEncoder;
+    private MailService mailService;
 
     @BeforeEach
-    public void setUp() {
-        Member member = new Member("test@naver.com", "홍길동",
-                "01012345678", LocalDate.parse("1999-03-31"),
-                "testpassword", MarketingAgree.BOTH, State.ACTIVATE);
-        member.changeFieldInfo(List.of("game", "computer"));
-        memberJpaRepository.save(member);
-    }
-
-    private String testMemberEmail = "asd@naver.com";
-    @Test
-    @DirtiesContext(methodMode = DirtiesContext.MethodMode.AFTER_METHOD)
-    public void 유저정보db저장및조회() throws Exception {
-        // given
-        MemberJoinDto memberJoinDto = new MemberJoinDto(testMemberEmail, "홍길동", "010-7444-1768", LocalDate.parse("1999-03-31"), "passwordTest", "passwordTest", MarketingAgree.BOTH, State.ACTIVATE);
-
-        // when
-        Member joinMember = memberService.join(memberJoinDto);
-
-        // then
-        assertAll(
-                () -> assertEquals(joinMember.getEmail(), testMemberEmail),
-                () -> assertEquals(joinMember.getName(), "홍길동")
-        );
-    }
-
-    @Test
-    @DirtiesContext(methodMode = DirtiesContext.MethodMode.AFTER_METHOD)
-    public void joinExceptionWIthPasswordIncorrect() {
-        // given
-        MemberJoinDto memberJoinDto = new MemberJoinDto(testMemberEmail, "홍길동", "010-7444-1768", LocalDate.parse("1999-03-31"), "passwordTest", "incorrectPassword", MarketingAgree.BOTH, State.ACTIVATE);
-
-        // when
-        // then
-        assertThatThrownBy(() -> memberService.join(memberJoinDto))
-                .isInstanceOf(ConfirmPasswordMismatchException.class);
-    }
-
-
-    @Test
-    @DirtiesContext(methodMode = DirtiesContext.MethodMode.AFTER_METHOD)
-    public void 회원가입성공() {
-        // given
-        MemberJoinDto memberJoinDto = MemberJoinDto.builder()
-                .email("asd@naver.com")
-                .name("홍길동")
-                .phoneNumber("010-7444-1768")
-                .birthDate(LocalDate.parse("1999-03-31"))
-                .password("passwordTest")
-                .passwordConfirm("passwordTest")
-                .marketingAgree(MarketingAgree.BOTH)
-                .userState(State.ACTIVATE)
-                .build();
-
-        HttpEntity<MemberJoinDto> request = new HttpEntity<>(memberJoinDto);
-
-        // when
-        ResponseEntity<String> response = restTemplate.postForEntity("/member", request, String.class);
-
-        // then
-        assertThat(response.getStatusCode()).isEqualTo(HttpStatus.CREATED);
-        assertThat(response.getBody()).contains("Member created successfully");
+    void setUp() {
+        memberRepository = new FakeMemberRepository();
+        passwordEncoder = mock(PasswordEncoder.class);
+        memberService = new MemberServiceImpl(memberRepository, passwordEncoder);
     }
 
-//    @Test
-//    @DirtiesContext(methodMode = DirtiesContext.MethodMode.AFTER_METHOD)
-//    public void 회원가입실패_비밀번호불일치() {
-//        // given
-//        MemberJoinDto memberJoinDto = MemberJoinDto.builder()
-//                .email("asd@naver.com")
-//                .name("홍길동")
-//                .phoneNumber("010-7444-1768")
-//                .birthDate(LocalDate.parse("1999-03-31"))
-//                .password("passwordTest")
-//                .passwordConfirm("wrongPassword")
-//                .marketingAgree(MarketingAgree.BOTH)
-//                .userState(State.ACTIVATE)
-//                .build();
-//
-//        HttpEntity<MemberJoinDto> request = new HttpEntity<>(memberJoinDto);
-//
-//        // when
-//        ResponseEntity<String> response = restTemplate.postForEntity("/member", request, String.class);
-//
-//        // then
-//        assertThat(response.getStatusCode()).isEqualTo(HttpStatus.BAD_REQUEST);
-//        assertThat(response.getBody()).contains("비밀번호가 일치하지 않습니다.");
-//    }
-
-    @Test
-    @DirtiesContext(methodMode = DirtiesContext.MethodMode.AFTER_METHOD)
-    public void 내정보_조회_성공() {
-        // Given
-
-        // When
-        ResponseEntity<MemberInfoResponse> response = restTemplate.getForEntity("/member/myPage/info", MemberInfoResponse.class);
-
-        // Then
-        assertEquals(HttpStatus.OK, response.getStatusCode());
-
-        MemberInfoResponse body = response.getBody();
-        assertNotNull(body);
-        assertEquals("test@naver.com", body.getEmail());
-        assertEquals("홍길동", body.getName());
-        assertEquals("01012345678", body.getPhoneNumber());
-        assertEquals(LocalDate.parse("1999-03-31"), body.getBirthDate());
-    }
-
-    @Test
-    @DirtiesContext(methodMode = DirtiesContext.MethodMode.AFTER_METHOD)
-    public void 내정보_수정() {
-        // Given
-
-        MemberInfoChangeDto changeDto = MemberInfoChangeDto.builder()
-                .phoneNumber("010-5678-1234")
-                .birthDate(LocalDate.parse("2000-01-01"))
-                .marketingAgree(MarketingAgree.EMAIL)
-                .build();
-
-        HttpEntity<MemberInfoChangeDto> requestEntity = new HttpEntity<>(changeDto);
-
-        // When
-        ResponseEntity<Boolean> response = restTemplate.exchange("/member/myPage/info", HttpMethod.PUT, requestEntity, Boolean.class);
-
-        // Then
-        assertEquals(HttpStatus.OK, response.getStatusCode());
-        Boolean body = response.getBody();
-        assertNotNull(body);
-        assertEquals(true, body);
-
-        // Verify changes
-        Member updatedMember = memberJpaRepository.findById(1L).orElse(null);
-        assertNotNull(updatedMember);
-        assertEquals("010-5678-1234", updatedMember.getPhoneNumber());
-        assertEquals(LocalDate.parse("2000-01-01"), updatedMember.getBirthDate());
-        assertEquals(MarketingAgree.EMAIL, updatedMember.getMarketingAgree());
-    }
-
-    @Test
-    @DirtiesContext(methodMode = DirtiesContext.MethodMode.AFTER_METHOD)
-    public void 관심분야_조회(){
-        // 회원추가
-
-        ResponseEntity<MemberFieldResponse> response = restTemplate.getForEntity("/member/myPage/field", MemberFieldResponse.class);
-
-        assertEquals(HttpStatus.OK, response.getStatusCode());
-        MemberFieldResponse body = response.getBody();
-        assertNotNull(body);
-        assertEquals(List.of("game", "computer"), body.getField());
-    }
-
-
-    @Test
-    @DirtiesContext(methodMode = DirtiesContext.MethodMode.AFTER_METHOD)
-    public void 관심분야_수정(){
-        //given
-
-        MemberFieldDto memberFieldDto = MemberFieldDto.builder().field(List.of("book", "movie")).build();
-        HttpEntity<MemberFieldDto> request = new HttpEntity<>(memberFieldDto);
-        //when
-        ResponseEntity<Boolean> response = restTemplate.postForEntity("/member/myPage/field", request, Boolean.class);
-        //then
-        assertEquals(HttpStatus.OK, response.getStatusCode());
-        Boolean body = response.getBody();
-        assertNotNull(body);
-        assertEquals(true, body);
-
-        Member updatedMember = memberJpaRepository.findById(1L).orElse(null);
-        assertNotNull(updatedMember);
-        assertEquals(List.of("book", "movie"), updatedMember.getField());
-    }
 }
\ No newline at end of file