diff --git a/src/vs/base/parts/tree/browser/treeView.ts b/src/vs/base/parts/tree/browser/treeView.ts
index cf6dc5ab8ff..5d56011feac 100644
--- a/src/vs/base/parts/tree/browser/treeView.ts
+++ b/src/vs/base/parts/tree/browser/treeView.ts
@@ -220,7 +220,7 @@ export class ViewItem implements IViewItem {
 			this.element.removeAttribute('id');
 		}
 		if (this.model.hasChildren()) {
-			this.element.setAttribute('aria-expanded', String(!!this.model.isExpanded()));
+			this.element.setAttribute('aria-expanded', String(!!this._styles['expanded']));
 		} else {
 			this.element.removeAttribute('aria-expanded');
 		}