diff --git a/jerry-core/ecma/operations/ecma-proxy-object.c b/jerry-core/ecma/operations/ecma-proxy-object.c
index 741fbbe79..bd75ea476 100644
--- a/jerry-core/ecma/operations/ecma-proxy-object.c
+++ b/jerry-core/ecma/operations/ecma-proxy-object.c
@@ -361,6 +361,7 @@ ecma_proxy_object_get_prototype_of (ecma_object_t *obj_p) /**< proxy object */
  *
  * See also:
  *          ECMAScript v6, 9.5.2
+ *          ECMAScript v11: 9.5.2
  *
  * Note: Returned value is always a simple value so freeing it is unnecessary.
  *
@@ -422,6 +423,12 @@ ecma_proxy_object_set_prototype_of (ecma_object_t *obj_p, /**< proxy object */
 
   ecma_free_value (trap_result);
 
+  /* ES11: 9 */
+  if (!boolean_trap_result)
+  {
+    return ecma_make_boolean_value (false);
+  }
+
   if (obj_p->u2.prototype_cp & JERRY_PROXY_SKIP_RESULT_VALIDATION)
   {
     return ecma_make_boolean_value (boolean_trap_result);
diff --git a/tests/test262-esnext-excludelist.xml b/tests/test262-esnext-excludelist.xml
index a75a184bf..dfbaad204 100644
--- a/tests/test262-esnext-excludelist.xml
+++ b/tests/test262-esnext-excludelist.xml
@@ -91,7 +91,6 @@
   <test id="built-ins/Object/entries/order-after-define-property.js"><reason></reason></test>
   <test id="built-ins/Object/keys/order-after-define-property.js"><reason></reason></test>
   <test id="built-ins/Proxy/preventExtensions/trap-is-undefined-target-is-proxy.js"><reason></reason></test>
-  <test id="built-ins/Proxy/setPrototypeOf/toboolean-trap-result-false.js"><reason></reason></test>
   <test id="built-ins/String/prototype/matchAll/regexp-is-undefined.js"><reason></reason></test>
   <test id="built-ins/String/prototype/normalize/form-is-not-valid-throws.js"><reason></reason></test>
   <test id="built-ins/String/prototype/normalize/length.js"><reason></reason></test>