diff --git a/Lib/test/test_multiprocessing.py b/Lib/test/test_multiprocessing.py
index 18066ba..d3620b7 100644
--- a/Lib/test/test_multiprocessing.py
+++ b/Lib/test/test_multiprocessing.py
@@ -1213,8 +1213,9 @@
 
     def test_rapid_restart(self):
         authkey = os.urandom(32)
+        port = test.support.find_unused_port()
         manager = QueueManager(
-            address=('localhost', 9999), authkey=authkey, serializer=SERIALIZER)
+            address=('localhost', port), authkey=authkey, serializer=SERIALIZER)
         manager.start()
 
         p = self.Process(target=self._putter, args=(manager.address, authkey))
@@ -1224,7 +1225,7 @@
         del queue
         manager.shutdown()
         manager = QueueManager(
-            address=('localhost', 9999), authkey=authkey, serializer=SERIALIZER)
+            address=('localhost', port), authkey=authkey, serializer=SERIALIZER)
         manager.start()
         manager.shutdown()