diff --git a/src/repository/Repository.ts b/src/repository/Repository.ts
index 1108e97fa8..587cb419dd 100644
--- a/src/repository/Repository.ts
+++ b/src/repository/Repository.ts
@@ -634,13 +634,13 @@ export class Repository<Entity extends ObjectLiteral> {
         //     ...this,
         //     ...custom
         // };
-        const thisRepo: any = this.constructor
+        const thisRepo = this.constructor as new (...args: any[]) => typeof this
         const { target, manager, queryRunner } = this
-        const cls = new (class extends thisRepo {
-            constructor() {
-                super(target, manager, queryRunner)
-            }
-        })()
+        const cls = new (class extends thisRepo {})(
+            target,
+            manager,
+            queryRunner,
+        )
         Object.assign(cls, custom)
         return cls as any
     }
diff --git a/src/repository/TreeRepository.ts b/src/repository/TreeRepository.ts
index 9a3bafdcf3..b105d61797 100644
--- a/src/repository/TreeRepository.ts
+++ b/src/repository/TreeRepository.ts
@@ -413,13 +413,13 @@ export class TreeRepository<Entity> extends Repository<Entity> {
         custom: CustomRepository &
             ThisType<TreeRepository<Entity> & CustomRepository>,
     ): TreeRepository<Entity> & CustomRepository {
-        const thisRepo: any = this.constructor
+        const thisRepo = this.constructor as new (...args: any[]) => typeof this
         const { target, manager, queryRunner } = this
-        const cls = new (class extends thisRepo {
-            constructor() {
-                super(target, manager, queryRunner)
-            }
-        })()
+        const cls = new (class extends thisRepo {})(
+            target,
+            manager,
+            queryRunner,
+        )
         Object.assign(cls, custom)
         return cls as any
     }
diff --git a/test/functional/custom-repository/custom-repository.test.ts b/test/functional/custom-repository/custom-repository.test.ts
index 45fc212078..ace137ebb3 100644
--- a/test/functional/custom-repository/custom-repository.test.ts
+++ b/test/functional/custom-repository/custom-repository.test.ts
@@ -43,7 +43,9 @@ describe("custom repository", () => {
                             await transactionalManager.withRepository(
                                 CustomRepository,
                             )
-                        await CustomRepository.save({ name: "Natures Prophet" })
+                        await transactionalCustomRepository.save({
+                            name: "Natures Prophet",
+                        })
                         const user =
                             await transactionalCustomRepository.findOneByName(
                                 "Natures Prophet",