diff --git a/requirements_dev.txt b/requirements_dev.txt
index 273f59b..54a14ed 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -2,7 +2,7 @@ pytest==4.6  # pyup: ignore
 pytest-runner==5.2
 bumpversion==0.6.0
 watchdog==0.10.3
-flake8==3.8.4
+flake8==6.0.0
 coverage==5.3
 cryptography==3.4.6
 Sphinx==3.3.1