diff --git a/.github/workflows/flux-local-diff.yaml b/.github/workflows/flux-local-diff.yaml
index ad098c5b..a7ddad3c 100644
--- a/.github/workflows/flux-local-diff.yaml
+++ b/.github/workflows/flux-local-diff.yaml
@@ -28,7 +28,7 @@ jobs:
         - kustomization
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
     - uses: ./action/diff
       id: diff
       with:
diff --git a/.github/workflows/flux-local-test.yaml b/.github/workflows/flux-local-test.yaml
index 9ee9a06e..a03b43c6 100644
--- a/.github/workflows/flux-local-test.yaml
+++ b/.github/workflows/flux-local-test.yaml
@@ -23,7 +23,7 @@ jobs:
         - tests/testdata/cluster6
         - tests/testdata/cluster7
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: ./action/test
       with:
         enable-helm: true
diff --git a/.github/workflows/lint.yaml b/.github/workflows/lint.yaml
index 303004c4..689ef207 100644
--- a/.github/workflows/lint.yaml
+++ b/.github/workflows/lint.yaml
@@ -17,7 +17,7 @@ jobs:
       fail-fast: false
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: codespell-project/actions-codespell@master
     - name: Run yamllint
       uses: ibiqlik/action-yamllint@v3
diff --git a/.github/workflows/pages.yaml b/.github/workflows/pages.yaml
index ae6c0b03..f527a7e7 100644
--- a/.github/workflows/pages.yaml
+++ b/.github/workflows/pages.yaml
@@ -33,7 +33,7 @@ jobs:
       matrix:
         python-version: ["3.10"]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v4
         with:
diff --git a/.github/workflows/python-package.yaml b/.github/workflows/python-package.yaml
index 3bd09184..428149f9 100644
--- a/.github/workflows/python-package.yaml
+++ b/.github/workflows/python-package.yaml
@@ -21,7 +21,7 @@ jobs:
         - "3.11"
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python-version }}
diff --git a/.github/workflows/python-publish.yaml b/.github/workflows/python-publish.yaml
index 6ddd781d..6aeb2b01 100644
--- a/.github/workflows/python-publish.yaml
+++ b/.github/workflows/python-publish.yaml
@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Set up Python
       uses: actions/setup-python@v4
       with:
diff --git a/action/diff/action.yml b/action/diff/action.yml
index 74c2b347..f35d7286 100644
--- a/action/diff/action.yml
+++ b/action/diff/action.yml
@@ -60,11 +60,11 @@ runs:
         pip install -e ${{ github.action_path }}/../../
       shell: bash
     - name: Checkout PR branch
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         path: pr
     - name: Checkout live branch
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         ref: ${{ inputs.live-branch }}
         path: live