diff --git a/.github/workflows/cmake-win64.yml b/.github/workflows/cmake-win64.yml
index cae9f2b2c..7174cf952 100644
--- a/.github/workflows/cmake-win64.yml
+++ b/.github/workflows/cmake-win64.yml
@@ -189,7 +189,7 @@ jobs:
 
       # FIXME: skip `string_reg` test (libtiff lzma build failure)
       - name: Test
-        run: ctest --test-dir build --build-config Release --output-on-failure --exclude-regex '^string_reg$'
+        run: ctest --test-dir build --build-config Release --output-on-failure --parallel 3 --exclude-regex '^string_reg$'
 
       - name: Install
         run: cmake --build build --config Release --target install
diff --git a/.github/workflows/cmake.yml b/.github/workflows/cmake.yml
index 04e73b798..6e0cefb23 100644
--- a/.github/workflows/cmake.yml
+++ b/.github/workflows/cmake.yml
@@ -68,7 +68,7 @@ jobs:
       run: cmake --build build --config ${{env.BUILD_TYPE}}
 
     - name: Test
-      run: ctest --test-dir build --build-config ${{env.BUILD_TYPE}} --output-on-failure
+      run: ctest --test-dir build --build-config ${{env.BUILD_TYPE}} --output-on-failure --parallel 3
 
     - name: Install
       run: sudo cmake --build build --config ${{env.BUILD_TYPE}} --target install