diff --git a/tests/__init__.py b/tests/__init__.py
index 8a054ed..a1cc234 100644
--- a/tests/__init__.py
+++ b/tests/__init__.py
@@ -6,6 +6,7 @@ import time
 from pathlib import Path
 from unittest import TestCase
 
+import psutil
 from aiohttp.test_utils import AioHTTPTestCase, unused_port
 from aiounittest import AsyncTestCase
 from click.testing import CliRunner
@@ -35,8 +36,11 @@ class BaseTestCase(TestCase):
     def terminate_dummy_processes(self):
         dummy_processes = []
         for process in get_root_process().children(recursive=True):
-            if str(self.DUMMY_EXE) in " ".join(process.cmdline()):
-                dummy_processes.append(process)
+            try:
+                if str(self.DUMMY_EXE) in " ".join(process.cmdline()):
+                    dummy_processes.append(process)
+            except psutil.NoSuchProcess:
+                continue
         terminate_processes(dummy_processes)
 
     def tearDown(self):