diff --git a/test/lib-test/TEST.ROOT b/test/lib-test/TEST.ROOT
index f23d38c1e66..33c9a9c2a43 100644
--- a/test/lib-test/TEST.ROOT
+++ b/test/lib-test/TEST.ROOT
@@ -31,6 +31,9 @@ keys=randomness
 # Minimum jtreg version
 requiredVersion=8.2.1+1
 
+# Prevent TestNG-based tests under this root, use @run junit actions instead
+disallowedActions=testng
+
 # Allow querying of various System properties in @requires clauses
 requires.extraPropDefns = ../jtreg-ext/requires/VMProps.java
 requires.extraPropDefns.bootlibs = ../lib/jdk/test/whitebox
diff --git a/test/lib-test/jdk/test/lib/jittester/MethodTemplateTest.java b/test/lib-test/jdk/test/lib/jittester/MethodTemplateTest.java
index 3cee24b4684..69751bc281c 100644
--- a/test/lib-test/jdk/test/lib/jittester/MethodTemplateTest.java
+++ b/test/lib-test/jdk/test/lib/jittester/MethodTemplateTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2025, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,8 +25,8 @@ package jdk.test.lib.jittester;
 
 import java.lang.reflect.Executable;
 
-import org.testng.annotations.Test;
-import static org.testng.Assert.*;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
 
 /*
  * @test
@@ -35,7 +35,7 @@ import static org.testng.Assert.*;
  * @library /test/lib
  *          /test/hotspot/jtreg/testlibrary/jittester/src
  *
- * @run testng jdk.test.lib.jittester.MethodTemplateTest
+ * @run junit jdk.test.lib.jittester.MethodTemplateTest
  */
 public class MethodTemplateTest {