diff --git a/backend/src/main/java/com/twtw/backend/domain/group/dto/request/MakeGroupDto.java b/backend/src/main/java/com/twtw/backend/domain/group/dto/request/MakeGroupDto.java
new file mode 100644
index 00000000..76520dcf
--- /dev/null
+++ b/backend/src/main/java/com/twtw/backend/domain/group/dto/request/MakeGroupDto.java
@@ -0,0 +1,13 @@
+package com.twtw.backend.domain.group.dto.request;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@NoArgsConstructor
+@AllArgsConstructor
+public class MakeGroupDto {
+    private String name;
+    private String groupImage;
+}
diff --git a/backend/src/main/java/com/twtw/backend/domain/group/dto/GroupInfoDto.java b/backend/src/main/java/com/twtw/backend/domain/group/dto/response/GroupInfoDto.java
similarity index 83%
rename from backend/src/main/java/com/twtw/backend/domain/group/dto/GroupInfoDto.java
rename to backend/src/main/java/com/twtw/backend/domain/group/dto/response/GroupInfoDto.java
index 210afae3..ca3329ac 100644
--- a/backend/src/main/java/com/twtw/backend/domain/group/dto/GroupInfoDto.java
+++ b/backend/src/main/java/com/twtw/backend/domain/group/dto/response/GroupInfoDto.java
@@ -1,4 +1,4 @@
-package com.twtw.backend.domain.group.dto;
+package com.twtw.backend.domain.group.dto.response;
 
 import lombok.AllArgsConstructor;
 import lombok.Getter;
diff --git a/backend/src/main/java/com/twtw/backend/domain/group/entity/Group.java b/backend/src/main/java/com/twtw/backend/domain/group/entity/Group.java
index b7c80de0..bc282706 100644
--- a/backend/src/main/java/com/twtw/backend/domain/group/entity/Group.java
+++ b/backend/src/main/java/com/twtw/backend/domain/group/entity/Group.java
@@ -22,6 +22,11 @@ public class Group {
     private String name;
     private String groupImage;
 
-    @OneToMany(mappedBy = "group")
+    @OneToMany(mappedBy = "group",cascade = {CascadeType.PERSIST,CascadeType.MERGE})
     private List<GroupMember> groupMembers = new ArrayList<>();
+
+    public Group(String name,String groupImage){
+        this.name = name;
+        this.groupImage = groupImage;
+    }
 }
diff --git a/backend/src/main/java/com/twtw/backend/domain/group/entity/GroupMember.java b/backend/src/main/java/com/twtw/backend/domain/group/entity/GroupMember.java
index c635dea5..e246ae59 100644
--- a/backend/src/main/java/com/twtw/backend/domain/group/entity/GroupMember.java
+++ b/backend/src/main/java/com/twtw/backend/domain/group/entity/GroupMember.java
@@ -26,4 +26,11 @@ public class GroupMember {
     @ManyToOne
     @JoinColumn(name = "member_id")
     private Member member;
+
+    public GroupMember(Group group,Member member){
+        this.group = group;
+        this.member = member;
+        group.getGroupMembers().add(this);
+        member.getGroupMembers().add(this);
+    }
 }
diff --git a/backend/src/main/java/com/twtw/backend/domain/group/mapper/GroupMapper.java b/backend/src/main/java/com/twtw/backend/domain/group/mapper/GroupMapper.java
new file mode 100644
index 00000000..98c5cc54
--- /dev/null
+++ b/backend/src/main/java/com/twtw/backend/domain/group/mapper/GroupMapper.java
@@ -0,0 +1,18 @@
+package com.twtw.backend.domain.group.mapper;
+
+import com.twtw.backend.domain.group.dto.request.MakeGroupDto;
+import com.twtw.backend.domain.group.entity.Group;
+import com.twtw.backend.domain.group.entity.GroupMember;
+import com.twtw.backend.domain.member.entity.Member;
+import org.springframework.stereotype.Component;
+
+@Component
+public class GroupMapper {
+    public GroupMember connectGroupMember(Group group, Member member){
+        return new GroupMember(group,member);
+    }
+
+    public Group toGroupEntity(MakeGroupDto groupDto){
+        return new Group(groupDto.getName(),groupDto.getGroupImage());
+    }
+}
diff --git a/backend/src/main/java/com/twtw/backend/domain/group/service/GroupService.java b/backend/src/main/java/com/twtw/backend/domain/group/service/GroupService.java
index 147e2f2a..c288200d 100644
--- a/backend/src/main/java/com/twtw/backend/domain/group/service/GroupService.java
+++ b/backend/src/main/java/com/twtw/backend/domain/group/service/GroupService.java
@@ -1,14 +1,59 @@
 package com.twtw.backend.domain.group.service;
 
+import com.twtw.backend.domain.group.dto.request.MakeGroupDto;
+import com.twtw.backend.domain.group.entity.Group;
+import com.twtw.backend.domain.group.entity.GroupMember;
+import com.twtw.backend.domain.group.mapper.GroupMapper;
+import com.twtw.backend.domain.group.repository.GroupMemberRepository;
 import com.twtw.backend.domain.group.repository.GroupRepository;
 
+import com.twtw.backend.domain.member.entity.Member;
+import com.twtw.backend.domain.member.service.AuthService;
+import com.twtw.backend.domain.member.service.MemberService;
+import com.twtw.backend.global.exception.EntityNotFoundException;
 import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.UUID;
 
 @Service
 public class GroupService {
     private final GroupRepository groupRepository;
-
-    public GroupService(GroupRepository groupRepository) {
+    private final GroupMemberRepository groupMemberRepository;
+    private final AuthService authService;
+    private final GroupMapper groupMapper;
+    private final MemberService memberService;
+    public GroupService(GroupRepository groupRepository,GroupMemberRepository groupMemberRepository,AuthService authService,GroupMapper groupMapper,MemberService memberService) {
         this.groupRepository = groupRepository;
+        this.groupMemberRepository = groupMemberRepository;
+        this.authService = authService;
+        this.groupMapper = groupMapper;
+        this.memberService = memberService;
+    }
+
+    @Transactional
+    public void makeGroup(MakeGroupDto groupDto){
+        Member member = this.authService.getMemberByJwt();
+        Group group = this.groupMapper.toGroupEntity(groupDto);
+
+        GroupMember groupMember = this.groupMapper.connectGroupMember(group,member);
+
+        groupMemberRepository.save(groupMember);
+    }
+    @Transactional
+    public void joinGroup(UUID groupId){
+        Member member = this.authService.getMemberByJwt();
+        Group group = this.groupRepository.findById(groupId).orElseThrow(EntityNotFoundException::new);
+
+        GroupMember groupMember = this.groupMapper.connectGroupMember(group,member);
+
+        groupMemberRepository.save(groupMember);
     }
+
+
+    public void removeGroup(UUID groupId){
+        // TODO()
+    }
+
+
 }
diff --git a/backend/src/main/java/com/twtw/backend/domain/member/entity/Member.java b/backend/src/main/java/com/twtw/backend/domain/member/entity/Member.java
index 4654903d..1bd955cd 100644
--- a/backend/src/main/java/com/twtw/backend/domain/member/entity/Member.java
+++ b/backend/src/main/java/com/twtw/backend/domain/member/entity/Member.java
@@ -30,7 +30,7 @@ public class Member {
 
     @Embedded private OAuth2Info oAuth2Info;
 
-    @OneToMany(mappedBy = "member")
+    @OneToMany(mappedBy = "member",cascade = {CascadeType.PERSIST,CascadeType.MERGE})
     private List<GroupMember> groupMembers = new ArrayList<>();
 
     public Member(String nickname, String profileImage) {
diff --git a/backend/src/test/java/com/twtw/backend/BackendApplicationTests.java b/backend/src/test/java/com/twtw/backend/BackendApplicationTests.java
index 4cfaf355..f41711ee 100644
--- a/backend/src/test/java/com/twtw/backend/BackendApplicationTests.java
+++ b/backend/src/test/java/com/twtw/backend/BackendApplicationTests.java
@@ -1,13 +1,15 @@
 package com.twtw.backend;
 
+import com.twtw.backend.domain.group.service.GroupService;
+import com.twtw.backend.domain.member.entity.Member;
 import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.test.context.ActiveProfiles;
 
 @SpringBootTest
 @ActiveProfiles("test")
 class BackendApplicationTests {
-
     @Test
     void contextLoads() {}
 }