diff --git a/src/syscall/js/js.go b/src/syscall/js/js.go
index bbf3de199b..e8d59638ba 100644
--- a/src/syscall/js/js.go
+++ b/src/syscall/js/js.go
@@ -414,7 +414,7 @@ func storeArgs(args []any, argValsDst []Value, argRefsDst []ref) {
 // It panics if v is not a JavaScript object.
 func (v Value) Length() int {
 	if vType := v.Type(); !vType.isObject() {
-		panic(&ValueError{"Value.SetIndex", vType})
+		panic(&ValueError{"Value.Length", vType})
 	}
 	r := valueLength(v.ref)
 	runtime.KeepAlive(v)