diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 368e610..cb38ae2 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -15,6 +15,10 @@ jobs:
         with:
           repository: ${{ github.event.pull_request.head.repo.full_name }}
           ref: ${{ github.head_ref }}
+      - name: modified files
+        run: |
+          modified_files=$(git diff --name-only --diff-filter=AM origin/${{ github.base_ref }..origin${{ github.head_ref }} | tr '\n' ' ')
+          echo "textlint_flags=$modified_files" >> $GITHUB_ENV
       - uses: tsuyoshicho/action-textlint@v3
         with:
           fail_on_error: true