diff --git a/requirements/dev.txt b/requirements/dev.txt
index 60a32b9bce..e257d5481a 100644
--- a/requirements/dev.txt
+++ b/requirements/dev.txt
@@ -7,7 +7,7 @@ pytest-cov==4.1.0
 # type checking and related stubs
 # mypy adds new rules in new minor versions, which could cause our PR check to fail
 # here we fix its version and upgrade it manually in the future
-mypy==1.8.0
+mypy==1.9.0
 types-pywin32==306.0.0.20240313
 types-PyYAML==6.0.12.20240311
 types-chevron==0.14.2.20240310