diff --git a/src/main/java/com/example/oneul/domain/post/service/command/PostCommnadServiceImpl.java b/src/main/java/com/example/oneul/domain/post/service/command/PostCommnadServiceImpl.java
index 489ba51..a8575f1 100644
--- a/src/main/java/com/example/oneul/domain/post/service/command/PostCommnadServiceImpl.java
+++ b/src/main/java/com/example/oneul/domain/post/service/command/PostCommnadServiceImpl.java
@@ -12,6 +12,7 @@ import org.springframework.transaction.annotation.Transactional;
 import com.example.oneul.domain.post.dao.command.PostCommandRepository;
 import com.example.oneul.domain.post.domain.Post;
 import com.example.oneul.domain.user.domain.UserEntity;
+import com.example.oneul.global.error.exception.ExpiredSessionException;
 import com.example.oneul.global.error.exception.NotFoundException;
 import com.example.oneul.infra.dto.PostMessage;
 import com.example.oneul.infra.kafka.KafkaPublisher;
@@ -85,7 +86,10 @@ public class PostCommnadServiceImpl implements PostCommandService{
     public void deletePost(Long id, HttpSession httpSession){
         // TODO: 이 때 세션이 만기되면 어떡함
         UserEntity userEntity = (UserEntity)httpSession.getAttribute("user");
-        
+        if(userEntity == null){
+            throw new ExpiredSessionException("만료된 세션");
+        }
+
         postCommandRepository.deleteByIdAndWriter(id, userEntity);
 
         kafkaPublisher.sendMessage(
diff --git a/src/main/java/com/example/oneul/global/error/GlobalExceptionHandler.java b/src/main/java/com/example/oneul/global/error/GlobalExceptionHandler.java
index 14177c4..4dae9ff 100644
--- a/src/main/java/com/example/oneul/global/error/GlobalExceptionHandler.java
+++ b/src/main/java/com/example/oneul/global/error/GlobalExceptionHandler.java
@@ -1,8 +1,5 @@
 package com.example.oneul.global.error;
 
-import com.example.oneul.domain.user.exception.UserAlreadyExistException;
-import com.example.oneul.domain.user.exception.WrongUsernameAndPasswordException;
-
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.http.HttpStatus;
@@ -10,6 +7,10 @@ import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.ControllerAdvice;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 
+import com.example.oneul.domain.user.exception.UserAlreadyExistException;
+import com.example.oneul.domain.user.exception.WrongUsernameAndPasswordException;
+import com.example.oneul.global.error.exception.ExpiredSessionException;
+
 @ControllerAdvice
 public class GlobalExceptionHandler {
     private static final Logger log = LoggerFactory.getLogger(GlobalExceptionHandler.class);
@@ -25,4 +26,10 @@ public class GlobalExceptionHandler {
         log.info(e.getMessage());
         return new ResponseEntity<>(e.getMessage(), HttpStatus.NOT_FOUND);
     }
+
+    @ExceptionHandler(ExpiredSessionException.class)
+    protected ResponseEntity<String> handleExpiredSessionException(ExpiredSessionException e){
+        log.info(e.getMessage());
+        return new ResponseEntity<>(e.getMessage(),HttpStatus.NOT_ACCEPTABLE);
+    }
 }
diff --git a/src/main/java/com/example/oneul/global/error/exception/ExpiredSessionException.java b/src/main/java/com/example/oneul/global/error/exception/ExpiredSessionException.java
new file mode 100644
index 0000000..17fb656
--- /dev/null
+++ b/src/main/java/com/example/oneul/global/error/exception/ExpiredSessionException.java
@@ -0,0 +1,11 @@
+package com.example.oneul.global.error.exception;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.bind.annotation.ResponseStatus;
+
+@ResponseStatus(code = HttpStatus.NOT_ACCEPTABLE, reason = "session is expired")
+public class ExpiredSessionException extends RuntimeException {
+    public ExpiredSessionException(String message){
+        super(message);
+    }
+}
diff --git a/src/test/java/com/example/oneul/service/PostCommandSerivceTest.java b/src/test/java/com/example/oneul/service/PostCommandSerivceTest.java
index 8737575..4375de3 100644
--- a/src/test/java/com/example/oneul/service/PostCommandSerivceTest.java
+++ b/src/test/java/com/example/oneul/service/PostCommandSerivceTest.java
@@ -1,5 +1,58 @@
 package com.example.oneul.service;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.BDDMockito.given;
+
+import java.util.Optional;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.springframework.mock.web.MockHttpSession;
+import org.springframework.test.context.ActiveProfiles;
+import org.springframework.test.util.ReflectionTestUtils;
+
+import com.example.oneul.domain.post.dao.command.PostCommandRepository;
+import com.example.oneul.domain.post.domain.Post;
+import com.example.oneul.domain.post.service.command.PostCommandService;
+import com.example.oneul.domain.post.service.command.PostCommnadServiceImpl;
+import com.example.oneul.infra.kafka.KafkaPublisher;
+
+@ActiveProfiles("test")
+@ExtendWith(MockitoExtension.class)
 public class PostCommandSerivceTest {
-    
+    private PostCommandService postCommandService;
+    @Mock private PostCommandRepository postCommandRepository;
+    @Mock private KafkaPublisher kafkaPublisher;
+    protected MockHttpSession httpSession;
+
+    @BeforeEach
+    public void setUp() throws Exception {
+        postCommandService = new PostCommnadServiceImpl(postCommandRepository, kafkaPublisher);
+    }
+
+    @Test
+    public void createPostTest() throws Exception {
+        // given
+        Long mockPostId = 1L;
+        Post post = mockPost(mockPostId);
+        ReflectionTestUtils.setField(post, "id", mockPostId);
+
+        // mocking
+        given(postCommandRepository.save(post)).willReturn(post);
+        given(postCommandRepository.findById(mockPostId)).willReturn(Optional.ofNullable(post));
+
+        // when
+        Post createdPost = postCommandService.createPost(post, httpSession);
+
+        // then
+        assertEquals(post.getContent(), createdPost.getContent());
+    }
+
+    private Post mockPost(Long id) {
+        return Post.builder().content("mocking post")
+                            .build();
+    }
 }
diff --git a/src/test/java/com/example/oneul/service/UserServiceTest.java b/src/test/java/com/example/oneul/service/UserServiceTest.java
index 4620039..a4a7025 100644
--- a/src/test/java/com/example/oneul/service/UserServiceTest.java
+++ b/src/test/java/com/example/oneul/service/UserServiceTest.java
@@ -28,11 +28,8 @@ import com.example.oneul.domain.user.service.UserServiceImpl;
 @ExtendWith(MockitoExtension.class)
 public class UserServiceTest {
     private UserService userService;
-    @Mock
-    private UserRepository userRepository;
-    @Mock
-    private PasswordEncoder passwordEncoder;
-
+    @Mock private UserRepository userRepository;
+    @Mock private PasswordEncoder passwordEncoder;
     protected MockHttpSession httpSession;
     
     @BeforeEach