diff --git a/.github/workflows/add_discussion_comment.yml b/.github/workflows/add_discussion_comment.yml
index 8ca2e9d..35dea01 100644
--- a/.github/workflows/add_discussion_comment.yml
+++ b/.github/workflows/add_discussion_comment.yml
@@ -81,7 +81,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 5
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Add Comment
         id: add_comment
         env:
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index 4defed5..0d46340 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -58,7 +58,7 @@ jobs:
       languages: ${{ steps.format.outputs.languages }}
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       # GitHub Actions組み込みのpathsによるフィルタでは、そのymlで実行する複数のjobそれぞれでpathsによる分岐ができない
       # そのため https://github.com/dorny/paths-filter を使い、フィルタのjob → 各jobの順で実行することで複数jobの分岐を実現する
diff --git a/.github/workflows/codeql_core.yml b/.github/workflows/codeql_core.yml
index 820a73c..1a33936 100644
--- a/.github/workflows/codeql_core.yml
+++ b/.github/workflows/codeql_core.yml
@@ -23,7 +23,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       # TODO: CodeQL が動作しないため暫定対応
       # 理想は inputs に java-version を持たせ引数にする
diff --git a/.github/workflows/create_gh_discussion.yml b/.github/workflows/create_gh_discussion.yml
index 657489f..4d64c78 100644
--- a/.github/workflows/create_gh_discussion.yml
+++ b/.github/workflows/create_gh_discussion.yml
@@ -65,7 +65,7 @@ jobs:
     timeout-minutes: 10
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
 
       - name: Run script
         id: create_discussion
diff --git a/.github/workflows/create_gh_issue.yml b/.github/workflows/create_gh_issue.yml
index 23e0f33..548e9ef 100644
--- a/.github/workflows/create_gh_issue.yml
+++ b/.github/workflows/create_gh_issue.yml
@@ -48,7 +48,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 5
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Create a issue
         run: |
           gh issue create \
diff --git a/.github/workflows/dependency_review.yml b/.github/workflows/dependency_review.yml
index f29d957..60ad5c6 100644
--- a/.github/workflows/dependency_review.yml
+++ b/.github/workflows/dependency_review.yml
@@ -36,7 +36,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 10
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: actions/dependency-review-action@v4
         with:
           comment-summary-in-pr: ${{ inputs.comment-summary-in-pr }}
diff --git a/.github/workflows/my_release.yml b/.github/workflows/my_release.yml
index e589a62..e232e7a 100644
--- a/.github/workflows/my_release.yml
+++ b/.github/workflows/my_release.yml
@@ -22,7 +22,7 @@ jobs:
         with:
           app-id: ${{ vars.ACTIONS_CI_APP_ID }}
           private-key: ${{ secrets.ACTIONS_CI_APP_PRIVATE_KEY }}
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           token: ${{ steps.app-token.outputs.token }}
       - name: tagpr
@@ -42,7 +42,7 @@ jobs:
     permissions:
       contents: write
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-tags: true
       - name: Git config
diff --git a/.github/workflows/my_test.yml b/.github/workflows/my_test.yml
index 3d93b85..ae5d44c 100644
--- a/.github/workflows/my_test.yml
+++ b/.github/workflows/my_test.yml
@@ -17,7 +17,7 @@ jobs:
       contents: read
       pull-requests: write
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Run actionlint with reviewdog
         uses: reviewdog/action-actionlint@e37e2ca68a70112d21e135229272da28ce2d0d5a # v1.66.1
         with:
@@ -30,5 +30,5 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 5
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: ls-lint/action@02e380fe8733d499cbfc9e22276de5085508a5bd # v2.3.1