diff --git a/requirements/base.txt b/requirements/base.txt
index a86072e4..83bee36a 100644
--- a/requirements/base.txt
+++ b/requirements/base.txt
@@ -4,6 +4,6 @@ Flask>=3.0.0,<4.0  # https://github.com/pallets/flask
 
 # Tools
 # ------------------------------------------------------------------------------
-typeguard==2.13.3  # https://github.com/agronholm/typeguard
+typeguard==4.1.5  # https://github.com/agronholm/typeguard
 typing_extensions>=4.3.0  # https://github.com/python/typing/blob/master/typing_extensions/README.rst
 typing_inspect==0.9.0  # https://github.com/ilevkivskyi/typing_inspect
diff --git a/requirements/ci.txt b/requirements/ci.txt
index 3d7779d2..dd05a159 100644
--- a/requirements/ci.txt
+++ b/requirements/ci.txt
@@ -23,7 +23,7 @@ pylint==3.0.3  # https://github.com/PyCQA/pylint
 mypy==1.8.0;python_version>="3.11"  # https://github.com/python/mypy
 pytype==2024.1.5;python_version>="3.10" and python_version<"3.12"  # https://github.com/google/pytype
 types_setuptools==69.0.0.20240115  # https://github.com/python/typeshed
-typeguard==2.13.3  # https://github.com/agronholm/typeguard
+typeguard==4.1.5  # https://github.com/agronholm/typeguard
 
 # Security check
 # ------------------------------------------------------------------------------
diff --git a/requirements/test.txt b/requirements/test.txt
index 7f4c5c4e..f6669619 100644
--- a/requirements/test.txt
+++ b/requirements/test.txt
@@ -10,7 +10,7 @@ mock==5.1.0  # https://github.com/testing-cabal/mock
 
 # Type check
 # ------------------------------------------------------------------------------
-typeguard==2.13.3  # https://github.com/agronholm/typeguard
+typeguard==4.1.5  # https://github.com/agronholm/typeguard
 
 # Code quality
 # ------------------------------------------------------------------------------