diff --git a/src/main/java/site/dogether/challengegroup/controller/ChallengeGroupController.java b/src/main/java/site/dogether/challengegroup/controller/ChallengeGroupController.java
index 33dabc6..c4c3673 100644
--- a/src/main/java/site/dogether/challengegroup/controller/ChallengeGroupController.java
+++ b/src/main/java/site/dogether/challengegroup/controller/ChallengeGroupController.java
@@ -68,6 +68,7 @@ public ResponseEntity<ApiResponse<JoinChallengeGroupResponse>> joinChallengeGrou
                             joinChallengeGroupDto.name(),
                             joinChallengeGroupDto.maximumMemberCount(),
                             joinChallengeGroupDto.startAt(),
+                            joinChallengeGroupDto.endAt(),
                             joinChallengeGroupDto.durationOption())
             ));
     }
diff --git a/src/main/java/site/dogether/challengegroup/controller/response/JoinChallengeGroupResponse.java b/src/main/java/site/dogether/challengegroup/controller/response/JoinChallengeGroupResponse.java
index 2b4bda7..9955a26 100644
--- a/src/main/java/site/dogether/challengegroup/controller/response/JoinChallengeGroupResponse.java
+++ b/src/main/java/site/dogether/challengegroup/controller/response/JoinChallengeGroupResponse.java
@@ -4,6 +4,7 @@ public record JoinChallengeGroupResponse(
     String name,
     int maximumMemberCount,
     String startAt,
+    String endAt,
     int durationOption
 ) {
 }
diff --git a/src/main/java/site/dogether/challengegroup/service/ChallengeGroupService.java b/src/main/java/site/dogether/challengegroup/service/ChallengeGroupService.java
index 180d16f..186e01e 100644
--- a/src/main/java/site/dogether/challengegroup/service/ChallengeGroupService.java
+++ b/src/main/java/site/dogether/challengegroup/service/ChallengeGroupService.java
@@ -1,5 +1,9 @@
 package site.dogether.challengegroup.service;
 
+import java.time.LocalDateTime;
+import java.time.format.DateTimeFormatter;
+import java.time.temporal.ChronoUnit;
+import java.util.List;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.stereotype.Service;
@@ -23,11 +27,6 @@
 import site.dogether.member.service.MemberService;
 import site.dogether.notification.service.NotificationService;
 
-import java.time.LocalDateTime;
-import java.time.format.DateTimeFormatter;
-import java.time.temporal.ChronoUnit;
-import java.util.List;
-
 @Slf4j
 @RequiredArgsConstructor
 @Transactional(readOnly = true)
@@ -109,11 +108,13 @@ public JoinChallengeGroupDto joinChallengeGroup(final String joinCode, final Str
 
         final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy.MM.dd");
         final String startAtFormatted = challengeGroupJpaEntity.getStartAt().format(formatter);
+        final String endAtFormatted = challengeGroupJpaEntity.getEndAt().format(formatter);
 
         return new JoinChallengeGroupDto(
                 joiningGroup.getName(),
                 joiningGroup.getMaximumMemberCount(),
                 startAtFormatted,
+                endAtFormatted,
                 joiningGroup.getDurationOption().getValue()
         );
     }
diff --git a/src/main/java/site/dogether/challengegroup/service/dto/JoinChallengeGroupDto.java b/src/main/java/site/dogether/challengegroup/service/dto/JoinChallengeGroupDto.java
index 4fffd36..82eb4fe 100644
--- a/src/main/java/site/dogether/challengegroup/service/dto/JoinChallengeGroupDto.java
+++ b/src/main/java/site/dogether/challengegroup/service/dto/JoinChallengeGroupDto.java
@@ -4,6 +4,7 @@ public record JoinChallengeGroupDto(
         String name,
         int maximumMemberCount,
         String startAt,
+        String endAt,
         int durationOption
 ) {
 }
diff --git a/src/test/java/site/dogether/docs/challengegroup/ChallengeGroupControllerDocsTest.java b/src/test/java/site/dogether/docs/challengegroup/ChallengeGroupControllerDocsTest.java
index e3721fa..64fd12c 100644
--- a/src/test/java/site/dogether/docs/challengegroup/ChallengeGroupControllerDocsTest.java
+++ b/src/test/java/site/dogether/docs/challengegroup/ChallengeGroupControllerDocsTest.java
@@ -1,5 +1,20 @@
 package site.dogether.docs.challengegroup;
 
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.Mockito.mock;
+import static org.springframework.restdocs.payload.PayloadDocumentation.fieldWithPath;
+import static org.springframework.restdocs.payload.PayloadDocumentation.requestFields;
+import static org.springframework.restdocs.payload.PayloadDocumentation.responseFields;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.delete;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+import static site.dogether.docs.util.DocumentLinkGenerator.DocUrl.CHALLENGE_GROUP_DURATION_OPTION;
+import static site.dogether.docs.util.DocumentLinkGenerator.DocUrl.CHALLENGE_GROUP_START_AT_OPTION;
+import static site.dogether.docs.util.DocumentLinkGenerator.generateLink;
+
+import java.util.List;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 import org.springframework.http.MediaType;
@@ -15,18 +30,6 @@
 import site.dogether.dailytodo.domain.Rank;
 import site.dogether.docs.util.RestDocsSupport;
 
-import java.util.List;
-
-import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.BDDMockito.given;
-import static org.mockito.Mockito.mock;
-import static org.springframework.restdocs.payload.PayloadDocumentation.*;
-import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.*;
-import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
-import static site.dogether.docs.util.DocumentLinkGenerator.DocUrl.CHALLENGE_GROUP_DURATION_OPTION;
-import static site.dogether.docs.util.DocumentLinkGenerator.DocUrl.CHALLENGE_GROUP_START_AT_OPTION;
-import static site.dogether.docs.util.DocumentLinkGenerator.generateLink;
-
 @DisplayName("챌린지 그룹 API 문서화 테스트")
 public class ChallengeGroupControllerDocsTest extends RestDocsSupport {
 
@@ -98,7 +101,7 @@ void joinChallengeGroup() throws Exception {
         final JoinChallengeGroupRequest request = new JoinChallengeGroupRequest("kelly-join-code");
 
         given(challengeGroupService.joinChallengeGroup(any(), any()))
-            .willReturn(new JoinChallengeGroupDto("성욱이와 친구들", 7, "2025.02.25", 7));
+            .willReturn(new JoinChallengeGroupDto("성욱이와 친구들", 7, "2025.02.17", "2025.02.23", 7));
 
         mockMvc.perform(
                 post("/api/groups/join")
@@ -128,6 +131,9 @@ void joinChallengeGroup() throws Exception {
                     fieldWithPath("data.startAt")
                         .description("챌린지 시작일")
                         .type(JsonFieldType.STRING),
+                    fieldWithPath("data.endAt")
+                        .description("챌린지 종료일")
+                        .type(JsonFieldType.STRING),
                     fieldWithPath("data.durationOption")
                         .description("챌린지 기간")
                         .type(JsonFieldType.NUMBER))));