diff --git a/backend/test/reactions/reactions.e2e-spec.ts b/backend/test/reactions/reactions.e2e-spec.ts
new file mode 100644
index 0000000..08e6df0
--- /dev/null
+++ b/backend/test/reactions/reactions.e2e-spec.ts
@@ -0,0 +1,245 @@
+import * as request from 'supertest';
+import { INestApplication } from '@nestjs/common';
+import { Test } from '@nestjs/testing';
+import { AppModule } from 'src/app.module';
+import { DataSource, QueryRunner } from 'typeorm';
+import { Diary } from 'src/diaries/entity/diary.entity';
+import { SocialType } from 'src/users/entity/socialType';
+import { DiaryStatus } from 'src/diaries/entity/diaryStatus';
+import { DiariesRepository } from 'src/diaries/diaries.repository';
+import { ReactionsRepository } from 'src/reactions/reactions.repository';
+import { UsersRepository } from 'src/users/users.repository';
+import { MoodDegree } from 'src/diaries/utils/diaries.constant';
+import * as cookieParser from 'cookie-parser';
+import { User } from 'src/users/entity/user.entity';
+import { testLogin } from 'test/utils/testLogin';
+
+describe('ReactionsController (e2e)', () => {
+  let app: INestApplication;
+  let queryRunner: QueryRunner;
+  let reactionsRepository: ReactionsRepository;
+  let diariesRepository: DiariesRepository;
+  let usersRepository: UsersRepository;
+
+  let user: User;
+  let accessToken: string;
+  let diary: Diary;
+  let url: string;
+
+  beforeAll(async () => {
+    const module = await Test.createTestingModule({
+      imports: [AppModule],
+    }).compile();
+
+    reactionsRepository = module.get<ReactionsRepository>(ReactionsRepository);
+    diariesRepository = module.get<DiariesRepository>(DiariesRepository);
+    usersRepository = module.get<UsersRepository>(UsersRepository);
+
+    const dataSource = module.get<DataSource>(DataSource);
+    queryRunner = dataSource.createQueryRunner();
+    dataSource.createQueryRunner = jest.fn();
+    queryRunner.release = jest.fn();
+    (dataSource.createQueryRunner as jest.Mock).mockReturnValue(queryRunner);
+
+    app = module.createNestApplication();
+    app.use(cookieParser());
+    await app.init();
+
+    jest.spyOn(reactionsRepository, 'save');
+    jest.spyOn(reactionsRepository, 'remove');
+
+    const userInfo = {
+      socialId: '1234',
+      socialType: SocialType.NAVER,
+      nickname: 'test',
+      email: 'test@abc.com',
+      profileImage: 'profile image',
+    };
+
+    user = await usersRepository.save(userInfo);
+    accessToken = await testLogin(user);
+
+    const diaryInfo = {
+      author: user,
+      title: '제목',
+      content: '<p>내용</p>',
+      thumbnail: null,
+      emotion: '🥰',
+      tagNames: ['일기', '안녕'],
+      status: DiaryStatus.PUBLIC,
+      summary: '일기 요약',
+      mood: MoodDegree.SO_SO,
+    };
+
+    diary = await diariesRepository.save(diaryInfo);
+    url = `/reactions/${diary.id}`;
+  });
+
+  afterAll(async () => {
+    await app.close();
+  });
+
+  beforeEach(async () => {
+    await queryRunner.startTransaction();
+  });
+
+  afterEach(async () => {
+    await queryRunner.rollbackTransaction();
+  });
+
+  describe('/reactions/:diaryId (GET)', () => {
+    it('특정 일기의 리액션 조회', async () => {
+      // given
+      const friendInfo = {
+        socialId: '12345',
+        socialType: SocialType.NAVER,
+        nickname: 'friend',
+        email: 'friend@abc.com',
+        profileImage: 'profile image',
+      };
+      const friend = await usersRepository.save(friendInfo);
+
+      await reactionsRepository.save({ user, diary, reaction: '🔥' });
+      await reactionsRepository.save({ user: friend, diary, reaction: '🥰' });
+
+      // when
+      const response = await request(app.getHttpServer())
+        .get(url)
+        .set('Cookie', [`utk=${accessToken}`]);
+
+      // then
+      expect(response.statusCode).toEqual(200);
+      expect(response.body.reactionList).toHaveLength(2);
+      expect(response.body.reactionList[0].reaction).toEqual('🔥');
+    });
+
+    it('일기의 리액션 없는 경우 빈 배열 반환', async () => {
+      // when
+      const response = await request(app.getHttpServer())
+        .get(url)
+        .set('Cookie', [`utk=${accessToken}`]);
+
+      // then
+      expect(response.statusCode).toEqual(200);
+      expect(response.body.reactionList).toEqual([]);
+    });
+  });
+
+  describe('/reactions/:diaryId (POST)', () => {
+    beforeEach(() => {
+      jest.clearAllMocks();
+    });
+
+    it('리액션 저장', async () => {
+      // when
+      const response = await request(app.getHttpServer())
+        .post(url)
+        .set('Cookie', [`utk=${accessToken}`])
+        .send({ reaction: '🥰' });
+
+      // then
+      expect(response.statusCode).toEqual(201);
+      expect(reactionsRepository.save).toHaveBeenCalled();
+    });
+
+    it('해당 일기에 이미 리액션을 남긴 경우 예외 발생', async () => {
+      // given
+      await reactionsRepository.save({ user, diary, reaction: '🔥' });
+
+      // when
+      const response = await request(app.getHttpServer())
+        .post(url)
+        .set('Cookie', [`utk=${accessToken}`])
+        .send({ reaction: '🥰' });
+
+      // then
+      expect(response.statusCode).toEqual(400);
+      expect(response.body.message).toEqual('이미 해당 글에 리액션을 남겼습니다.');
+      expect(reactionsRepository.save).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  describe('/reactions/:diaryId (PUT)', () => {
+    beforeEach(() => {
+      jest.clearAllMocks();
+    });
+
+    it('리액션 수정', async () => {
+      // given
+      await reactionsRepository.save({ user, diary, reaction: '🔥' });
+
+      // when
+      const response = await request(app.getHttpServer())
+        .put(url)
+        .set('Cookie', [`utk=${accessToken}`])
+        .send({ reaction: '🥰' });
+
+      // then
+      expect(response.statusCode).toEqual(200);
+      expect(reactionsRepository.save).toHaveBeenCalledTimes(2);
+    });
+
+    it('리액션이 존재하지 않는데 해당 요청을 보낸 경우 예외 발생', async () => {
+      // when
+      const response = await request(app.getHttpServer())
+        .put(url)
+        .set('Cookie', [`utk=${accessToken}`])
+        .send({ reaction: '🥰' });
+
+      // then
+      expect(response.statusCode).toEqual(400);
+      expect(response.body.message).toEqual('리액션 기록이 존재하지 않습니다.');
+      expect(reactionsRepository.save).toHaveBeenCalledTimes(0);
+    });
+  });
+
+  describe('/reactions/:diaryId (DELETE)', () => {
+    beforeEach(() => {
+      jest.clearAllMocks();
+    });
+
+    it('리액션 삭제', async () => {
+      // given
+      await reactionsRepository.save({ user, diary, reaction: '🔥' });
+
+      // when
+      const response = await request(app.getHttpServer())
+        .delete(url)
+        .set('Cookie', [`utk=${accessToken}`])
+        .send({ reaction: '🔥' });
+
+      // then
+      expect(response.statusCode).toEqual(200);
+      expect(reactionsRepository.remove).toHaveBeenCalled();
+    });
+
+    it('삭제하려는 리액션이 존재하지 않는 경우 예외 발생', async () => {
+      // when
+      const response = await request(app.getHttpServer())
+        .delete(url)
+        .set('Cookie', [`utk=${accessToken}`])
+        .send({ reaction: '🔥' });
+
+      // then
+      expect(response.statusCode).toEqual(400);
+      expect(response.body.message).toEqual('이미 삭제된 리액션 정보입니다.');
+      expect(reactionsRepository.remove).toHaveBeenCalledTimes(0);
+    });
+
+    it('기존에 남긴 리액션과 삭제하려는 리액션이 일치하지 않는 경우 예외 발생', async () => {
+      // given
+      await reactionsRepository.save({ user, diary, reaction: '🔥' });
+
+      // when
+      const response = await request(app.getHttpServer())
+        .delete(url)
+        .set('Cookie', [`utk=${accessToken}`])
+        .send({ reaction: '🥰' });
+
+      // then
+      expect(response.statusCode).toEqual(400);
+      expect(response.body.message).toEqual('이미 삭제된 리액션 정보입니다.');
+      expect(reactionsRepository.remove).toHaveBeenCalledTimes(0);
+    });
+  });
+});