diff --git a/lib/internal/test_runner/mock/mock_timers.js b/lib/internal/test_runner/mock/mock_timers.js
index 643128c3f0031f..69f62357b0d7bf 100644
--- a/lib/internal/test_runner/mock/mock_timers.js
+++ b/lib/internal/test_runner/mock/mock_timers.js
@@ -92,6 +92,10 @@ class Timeout {
   refresh() {
     return this;
   }
+
+  [SymbolDispose]() {
+    globalThis.clearTimeout(this);
+  }
 }
 
 class MockTimers {