diff --git a/src/test/java/com/example/g8backend/service/CommentServiceTest.java b/src/test/java/com/example/g8backend/service/CommentServiceTest.java
new file mode 100644
index 0000000..f76880a
--- /dev/null
+++ b/src/test/java/com/example/g8backend/service/CommentServiceTest.java
@@ -0,0 +1,125 @@
+package com.example.g8backend.service;
+
+import com.example.g8backend.entity.Comment;
+import com.example.g8backend.mapper.CommentMapper;
+import com.example.g8backend.service.impl.CommentServiceImpl;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
+
+import java.util.Arrays;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.*;
+
+@ExtendWith(SpringExtension.class)
+@DisplayName("评论服务测试")
+class CommentServiceTest {
+
+    @Mock
+    private CommentMapper commentMapper;
+
+    @InjectMocks
+    private CommentServiceImpl commentService;
+
+    private Comment testComment;
+
+    @BeforeEach
+    void setUp() {
+        MockitoAnnotations.openMocks(this);
+        testComment = createTestComment();
+    }
+
+    private Comment createTestComment() {
+        Comment comment = new Comment();
+        comment.setCommentId(1L);
+        comment.setPostId(1L);
+        comment.setUserId(1L);
+        comment.setContent("测试评论内容");
+        return comment;
+    }
+
+    @Test
+    @DisplayName("创建评论-成功")
+    void createComment_ShouldSucceed() {
+        // Arrange
+        when(commentMapper.insert(any(Comment.class))).thenReturn(1);
+
+        // Act
+        commentService.createComment(1L, 1L, "测试评论内容", null);
+
+        // Assert
+        verify(commentMapper).insert(any(Comment.class));
+    }
+
+    @Test
+    @DisplayName("获取评论-根据帖子ID返回评论列表")
+    void getCommentsByPostId_ShouldReturnComments() {
+        // Arrange
+        List<Comment> expectedComments = Arrays.asList(testComment);
+        when(commentMapper.findTopLevelCommentsByPostId(1L)).thenReturn(expectedComments);
+
+        // Act
+        List<Comment> result = commentService.getCommentsByPostId(1L);
+
+        // Assert
+        assertNotNull(result);
+        assertFalse(result.isEmpty());
+        assertEquals(testComment.getCommentId(), result.get(0).getCommentId());
+        verify(commentMapper).findTopLevelCommentsByPostId(1L);
+    }
+
+    @Test
+    @DisplayName("删除评论-成功")
+    void deleteComment_ShouldSucceed() {
+        // Arrange
+        when(commentMapper.deleteById(1L)).thenReturn(1);
+
+        // Act
+        boolean result = commentService.deleteComment(1L);
+
+        // Assert
+        assertTrue(result);
+        verify(commentMapper).deleteById(1L);
+    }
+
+    @Test
+    @DisplayName("获取评论-没有评论")
+    void getCommentsByPostId_WhenNoComments_ShouldReturnEmptyList() {
+        // Arrange
+        when(commentMapper.findTopLevelCommentsByPostId(999L)).thenReturn(Arrays.asList());
+
+        // Act
+        List<Comment> result = commentService.getCommentsByPostId(999L);
+
+        // Assert
+        assertNotNull(result);
+        assertTrue(result.isEmpty());
+        verify(commentMapper).findTopLevelCommentsByPostId(999L);
+    }
+
+    @Test
+    @DisplayName("获取评论-根据父评论ID返回子评论")
+    void getReplies_ShouldReturnReplies() {
+        // Arrange
+        List<Comment> expectedReplies = Arrays.asList(testComment);
+        when(commentMapper.findRepliesByParentCommentId(1L)).thenReturn(expectedReplies);
+
+        // Act
+        List<Comment> result = commentService.getReplies(1L, 5);
+
+        // Assert
+        assertNotNull(result);
+        assertFalse(result.isEmpty());
+        assertEquals(testComment.getCommentId(), result.get(0).getCommentId());
+        verify(commentMapper).findRepliesByParentCommentId(1L);
+    }
+
+}