diff --git a/backend/src/entities/group/use-cases/remove-user-from-group.use.case.ts b/backend/src/entities/group/use-cases/remove-user-from-group.use.case.ts
index 20719b18a..d7be2beae 100644
--- a/backend/src/entities/group/use-cases/remove-user-from-group.use.case.ts
+++ b/backend/src/entities/group/use-cases/remove-user-from-group.use.case.ts
@@ -23,7 +23,7 @@ export class RemoveUserFromGroupUseCase
   protected async implementation(inputData: AddUserInGroupDs): Promise<RemoveUserFromGroupResultDs> {
     const { groupId } = inputData;
     const email = inputData.email.toLowerCase();
-    const foundUser = await this._dbContext.userRepository.findOneUserByEmail(email);
+    const foundUser = await this._dbContext.userRepository.findOneUserByEmailAndGroupId(email, groupId);
     if (!foundUser) {
       throw new HttpException(
         {
@@ -47,6 +47,14 @@ export class RemoveUserFromGroupUseCase
         return e.id;
       })
       .indexOf(foundUser.id);
+    if (delIndex === -1) {
+      throw new HttpException(
+        {
+          message: Messages.USER_NOT_FOUND,
+        },
+        HttpStatus.NOT_FOUND,
+      );
+    }
     groupToUpdate.users.splice(delIndex, 1);
     const updatedGroup = await this._dbContext.groupRepository.saveNewOrUpdatedGroup(groupToUpdate);
     return buildRemoveUserFromGroupResultDs(updatedGroup);
diff --git a/backend/src/entities/user/repository/user-custom-repository-extension.ts b/backend/src/entities/user/repository/user-custom-repository-extension.ts
index 1338949d9..74fb251ee 100644
--- a/backend/src/entities/user/repository/user-custom-repository-extension.ts
+++ b/backend/src/entities/user/repository/user-custom-repository-extension.ts
@@ -59,6 +59,14 @@ export const userCustomRepositoryExtension: IUserRepository = {
     return userQb.getOne();
   },
 
+  async findOneUserByEmailAndGroupId(email: string, groupId: string): Promise<UserEntity> {
+    const userQb = this.createQueryBuilder('user')
+      .leftJoinAndSelect('user.groups', 'group')
+      .where('user.email = :userEmail', { userEmail: email?.toLowerCase() })
+      .andWhere('group.id = :groupId', { groupId: groupId });
+    return await userQb.getOne();
+  },
+
   async findOneUserWithEmailVerification(userId: string): Promise<UserEntity> {
     const usersQb = this.createQueryBuilder('user')
       .leftJoinAndSelect('user.email_verification', 'email_verification')
diff --git a/backend/src/entities/user/repository/user.repository.interface.ts b/backend/src/entities/user/repository/user.repository.interface.ts
index 90f32192c..cc388fb27 100644
--- a/backend/src/entities/user/repository/user.repository.interface.ts
+++ b/backend/src/entities/user/repository/user.repository.interface.ts
@@ -57,4 +57,6 @@ export interface IUserRepository {
   unSuspendUsers(userIds: Array<string>): Promise<Array<UserEntity>>;
 
   bulkSaveUpdatedUsers(updatedUsers: Array<UserEntity>): Promise<Array<UserEntity>>;
+
+  findOneUserByEmailAndGroupId(email: string, groupId: string): Promise<UserEntity>;
 }