diff --git a/src/utils/deep-clone.ts b/src/utils/deep-clone.ts
index 44aada0e6..bc2b88e2d 100644
--- a/src/utils/deep-clone.ts
+++ b/src/utils/deep-clone.ts
@@ -1,12 +1,21 @@
-import { deepAssign } from './deep-assign';
+import {isDef} from "./base";
+
+export function deepClone<T extends Record<string, any> | null | undefined>(obj: T): T {
+  if (!isDef(obj)) {
+    return obj;
+  }
 
-export function deepClone<T extends Record<string, any>>(obj: T): T {
   if (Array.isArray(obj)) {
     return (obj.map((item) => deepClone(item)) as unknown) as T;
   }
 
   if (typeof obj === 'object') {
-    return deepAssign({}, obj) as T;
+    const to = {} as Record<string, any>;
+    Object.keys(obj).forEach((key) => {
+      to[key] = deepClone(obj[key]);
+    });
+
+    return to as T;
   }
 
   return obj;
diff --git a/src/utils/test/index.spec.ts b/src/utils/test/index.spec.ts
index c64c76034..656a2b489 100644
--- a/src/utils/test/index.spec.ts
+++ b/src/utils/test/index.spec.ts
@@ -11,9 +11,11 @@ import { addUnit, unitToPx } from '../format/unit';
 test('deepClone', () => {
   const a = { foo: 0 };
   const b = { foo: 0, bar: 1 };
+  const c = null;
   const arr = [a, b];
   expect(deepClone(a)).toEqual(a);
   expect(deepClone(b)).toEqual(b);
+  expect(deepClone(c)).toEqual(c);
   expect(deepClone(noop)).toEqual(noop);
   expect(deepClone(arr)).toEqual(arr);
 });