diff --git a/npm/ng-packs/packages/components/tree/src/lib/components/tree.component.ts b/npm/ng-packs/packages/components/tree/src/lib/components/tree.component.ts
index c61b9c3f22..f18c8e29f2 100644
--- a/npm/ng-packs/packages/components/tree/src/lib/components/tree.component.ts
+++ b/npm/ng-packs/packages/components/tree/src/lib/components/tree.component.ts
@@ -36,6 +36,7 @@ export class TreeComponent {
   @Output() readonly expandedKeysChange = new EventEmitter<string[]>();
   @Output() readonly selectedNodeChange = new EventEmitter();
   @Output() readonly dropOver = new EventEmitter<DropEvent>();
+  @Output() readonly nzExpandChange = new EventEmitter<NzFormatEmitEvent>();
   @Input() noAnimation = true;
   @Input() draggable: boolean;
   @Input() checkable: boolean;
@@ -71,6 +72,7 @@ export class TreeComponent {
   onExpandedKeysChange(event) {
     this.expandedKeys = [...event.keys];
     this.expandedKeysChange.emit(event.keys);
+    this.nzExpandChange.emit(event);
   }
 
   onDrop(event: DropEvent) {
diff --git a/npm/ng-packs/packages/components/tree/src/lib/utils/nz-tree-adapter.ts b/npm/ng-packs/packages/components/tree/src/lib/utils/nz-tree-adapter.ts
index d5d32f0146..0130b2f2c0 100644
--- a/npm/ng-packs/packages/components/tree/src/lib/utils/nz-tree-adapter.ts
+++ b/npm/ng-packs/packages/components/tree/src/lib/utils/nz-tree-adapter.ts
@@ -5,7 +5,7 @@ export abstract class BaseNode {
   constructor(public id: string, public parentId: string | null) {}
 }
 
-class TreeNode<T extends BaseNode> extends BaseNode {
+export class TreeNode<T extends BaseNode> extends BaseNode {
   title: string | undefined;
   key: string;
   icon: string | null = null;
@@ -89,7 +89,6 @@ function createTreeFromList<T extends BaseNode>(list: T[]): TreeNode<T>[] {
       tree.push(node);
     }
   });
-
   return tree;
 }