diff --git a/.github/workflows/autoformat.js b/.github/workflows/autoformat.js
index ca76af3d415fd..e4051a8cf76da 100644
--- a/.github/workflows/autoformat.js
+++ b/.github/workflows/autoformat.js
@@ -13,14 +13,21 @@ const createCommitStatus = async (context, github, sha, state) => {
   });
 };
 
-const createStatus = async (context, github) => {
+const createStatus = async (context, github, core) => {
   const { owner, repo } = context.repo;
   const pull_number = context.issue.number;
   const pr = await github.pulls.get({ owner, repo, pull_number });
-  const { sha, ref } = pr.data.head;
+  const {
+    sha,
+    ref,
+    repo: { full_name },
+  } = pr.data.head;
   await createCommitStatus(context, github, sha, 'pending');
+  if (full_name === 'mlflow/mlflow' && ref === 'master') {
+    core.setFailed('Running autoformat bot against master branch of mlflow/mlflow is not allowed.');
+  }
   return {
-    repository: `${owner}/${repo}`,
+    repository: full_name,
     pull_number,
     sha,
     ref,
diff --git a/.github/workflows/autoformat.yml b/.github/workflows/autoformat.yml
index a70407c0a1dab..609bf6489137d 100644
--- a/.github/workflows/autoformat.yml
+++ b/.github/workflows/autoformat.yml
@@ -36,7 +36,7 @@ jobs:
           github-token: ${{ secrets.GITHUB_TOKEN }}
           script: |
             const autoformat = require('./.github/workflows/autoformat.js');
-            return await autoformat.createStatus(context, github);
+            return await autoformat.createStatus(context, github, core);
 
   check-diff:
     runs-on: ubuntu-latest
@@ -55,7 +55,7 @@ jobs:
       - name: Check diff
         id: check-diff
         run: |
-          repository="${{ needs.check-comment.outputs.repository }}"
+          repository="${{ github.repository }}"
           pull_number="${{ needs.check-comment.outputs.pull_number }}"
           changed_files="$(python dev/list_changed_files.py --repository $repository --pr-num $pull_number)"
           py_changed=$([[ -z $(echo "$changed_files" | grep '\.py$') ]] && echo "false" || echo "true")