diff --git a/Lib/concurrent/futures/process.py b/Lib/concurrent/futures/process.py
--- a/Lib/concurrent/futures/process.py
+++ b/Lib/concurrent/futures/process.py
@@ -273,9 +273,6 @@
                 if not pending_work_items:
                     shutdown_worker()
                     return
-                else:
-                    # Start shutting down by telling a process it can exit.
-                    call_queue.put_nowait(None)
             except Full:
                 # This is not a problem: we will eventually be woken up (in
                 # result_queue.get()) and be able to send a sentinel again.
diff --git a/Lib/test/test_concurrent_futures.py b/Lib/test/test_concurrent_futures.py
--- a/Lib/test/test_concurrent_futures.py
+++ b/Lib/test/test_concurrent_futures.py
@@ -400,6 +400,11 @@
         # Submitting other jobs fails as well.
         self.assertRaises(BrokenProcessPool, self.executor.submit, pow, 2, 8)
 
+    def test_hang_issue12364(self):
+        fs = [self.executor.submit(time.sleep, 0.1) for _ in range(50)]
+        self.executor.shutdown()
+        for f in fs:
+            f.result()
 
 class FutureTests(unittest.TestCase):
     def test_done_callback_with_result(self):