diff --git a/packages/runtime-dom/src/apiCustomElement.ts b/packages/runtime-dom/src/apiCustomElement.ts
index 5ff45d652f2..9dd35bf7638 100644
--- a/packages/runtime-dom/src/apiCustomElement.ts
+++ b/packages/runtime-dom/src/apiCustomElement.ts
@@ -179,7 +179,11 @@ export class VueElement extends BaseClass {
   connectedCallback() {
     this._connected = true
     if (!this._instance) {
-      this._resolveDef()
+      if (this._resolved) {
+        this._update()
+      } else {
+        this._resolveDef()
+      }
     }
   }
 
@@ -197,9 +201,6 @@ export class VueElement extends BaseClass {
    * resolve inner component definition (handle possible async component)
    */
   private _resolveDef() {
-    if (this._resolved) {
-      return
-    }
     this._resolved = true
 
     // set initial attrs