diff --git a/spark/src/main/scala/org/apache/comet/serde/QueryPlanSerde.scala b/spark/src/main/scala/org/apache/comet/serde/QueryPlanSerde.scala
index 7238990ad..8c7ef3d11 100644
--- a/spark/src/main/scala/org/apache/comet/serde/QueryPlanSerde.scala
+++ b/spark/src/main/scala/org/apache/comet/serde/QueryPlanSerde.scala
@@ -2073,6 +2073,13 @@ object QueryPlanSerde extends Logging with ShimQueryPlanSerde with CometExprShim
             scalarExprToProtoWithReturnType(algorithm, StringType, childExpr)
           }
 
+        case Base64(child) =>
+          val castExpr = Cast(child, StringType)
+          val childExpr = exprToProtoInternal(castExpr, inputs)
+          val encoding = exprToProtoInternal(Literal("base64"), inputs)
+          val optExpr = scalarExprToProto("encode", childExpr, encoding)
+          optExprWithInfo(optExpr, expr, castExpr)
+
         case _ =>
           withInfo(expr, s"${expr.prettyName} is not supported", expr.children: _*)
           None
diff --git a/spark/src/test/scala/org/apache/comet/CometExpressionSuite.scala b/spark/src/test/scala/org/apache/comet/CometExpressionSuite.scala
index 28027c5cb..58b372c2b 100644
--- a/spark/src/test/scala/org/apache/comet/CometExpressionSuite.scala
+++ b/spark/src/test/scala/org/apache/comet/CometExpressionSuite.scala
@@ -1467,4 +1467,22 @@ class CometExpressionSuite extends CometTestBase with AdaptiveSparkPlanHelper {
     }
   }
 
+  test("base64") {
+    val table = "test"
+    withTable(table) {
+      sql(s"create table $table(col string) using parquet")
+      sql(s"""INSERT INTO $table VALUES
+             |('537061726B2053514C'),
+             |('737472696E67'),
+             |('\\0'),
+             |(''),
+             |('###'),
+             |('G123'),
+             |('hello'),
+             |('A1B'),
+             |('0A1B')""".stripMargin)
+
+      checkSparkAnswerAndOperator(s"SELECT base64(col) FROM $table")
+    }
+  }
 }