diff --git a/.github/scripts/check_team_membership.js b/.github/scripts/check_team_membership.js
index ca8e75f1d13..46705d648ef 100644
--- a/.github/scripts/check_team_membership.js
+++ b/.github/scripts/check_team_membership.js
@@ -1,25 +1,38 @@
 // Copyright (c) Microsoft. All rights reserved.
 
 /**
- * Resolve the issue author and check their team membership.
+ * Resolve the issue or pull request author and check their team membership.
  *
  * @param {object} opts
  * @param {object} opts.github - Octokit REST client from actions/github-script
  * @param {object} opts.context - GitHub Actions context
  * @param {object} opts.core - GitHub Actions core toolkit
  * @param {string} opts.teamSlug - Team slug to check membership against
- * @param {string|number} opts.issueNumber - Issue number to resolve author for
+ * @param {string|number} opts.issueNumber - Issue or pull request number to resolve author for
  * @returns {Promise<{author: string|null, isTeamMember: boolean}>}
  */
 async function checkTeamMembership({ github, context, core, teamSlug, issueNumber }) {
-  let author = context.payload.issue?.user?.login;
+  let author =
+    context.payload.issue?.user?.login ??
+    context.payload.pull_request?.user?.login;
+
   if (!author) {
-    const { data: issue } = await github.rest.issues.get({
-      owner: context.repo.owner,
-      repo: context.repo.repo,
-      issue_number: Number(issueNumber),
-    });
-    author = issue.user?.login;
+    const number = Number(issueNumber);
+    if (context.payload.pull_request) {
+      const { data: pr } = await github.rest.pulls.get({
+        owner: context.repo.owner,
+        repo: context.repo.repo,
+        pull_number: number,
+      });
+      author = pr.user?.login;
+    } else {
+      const { data: issue } = await github.rest.issues.get({
+        owner: context.repo.owner,
+        repo: context.repo.repo,
+        issue_number: number,
+      });
+      author = issue.user?.login;
+    }
   }
 
   if (!author) {
diff --git a/.github/tests/test_check_team_membership.js b/.github/tests/test_check_team_membership.js
index 6fbec9ff609..2e35135b9e7 100644
--- a/.github/tests/test_check_team_membership.js
+++ b/.github/tests/test_check_team_membership.js
@@ -16,7 +16,12 @@ const checkTeamMembership = require('../scripts/check_team_membership.js');
 // Helpers
 // ---------------------------------------------------------------------------
 
-function createMocks({ payloadIssue = undefined, apiUser = 'api-user', teamState = 'active' } = {}) {
+function createMocks({
+  payloadIssue = undefined,
+  payloadPullRequest = undefined,
+  apiUser = 'api-user',
+  teamState = 'active',
+} = {}) {
   const core = {
     _infoMessages: [],
     _failedMessages: [],
@@ -24,8 +29,16 @@ function createMocks({ payloadIssue = undefined, apiUser = 'api-user', teamState
     setFailed(msg) { this._failedMessages.push(msg); },
   };
 
+  const payload = {};
+  if (payloadIssue !== undefined) {
+    payload.issue = payloadIssue;
+  }
+  if (payloadPullRequest !== undefined) {
+    payload.pull_request = payloadPullRequest;
+  }
+
   const context = {
-    payload: { issue: payloadIssue },
+    payload,
     repo: { owner: 'test-org', repo: 'test-repo' },
   };
 
@@ -36,6 +49,11 @@ function createMocks({ payloadIssue = undefined, apiUser = 'api-user', teamState
           data: { user: apiUser ? { login: apiUser } : null },
         }),
       },
+      pulls: {
+        get: async () => ({
+          data: { user: apiUser ? { login: apiUser } : null },
+        }),
+      },
       teams: {
         getByName: async () => ({}),
         getMembershipForUserInOrg: async () => ({
@@ -64,6 +82,37 @@ describe('author resolution', () => {
     assert.equal(result.author, 'payload-user');
   });
 
+  it('resolves author from pull_request event payload', async () => {
+    const { github, context, core } = createMocks({
+      payloadPullRequest: { user: { login: 'pr-author' } },
+    });
+    let issuesGetCalled = false;
+    github.rest.issues.get = async () => {
+      issuesGetCalled = true;
+      return { data: { user: { login: 'api-user' } } };
+    };
+
+    const result = await checkTeamMembership({ github, context, core, ...BASE_OPTS });
+    assert.equal(result.author, 'pr-author');
+    assert.equal(issuesGetCalled, false);
+  });
+
+  it('resolves author via pulls API when pull_request payload user is null', async () => {
+    const { github, context, core } = createMocks({
+      payloadPullRequest: { user: null },
+      apiUser: 'fetched-pr-author',
+    });
+    let pullsGetCalled = false;
+    github.rest.pulls.get = async () => {
+      pullsGetCalled = true;
+      return { data: { user: { login: 'fetched-pr-author' } } };
+    };
+
+    const result = await checkTeamMembership({ github, context, core, ...BASE_OPTS });
+    assert.equal(result.author, 'fetched-pr-author');
+    assert.equal(pullsGetCalled, true);
+  });
+
   it('resolves author via API when payload issue is absent', async () => {
     const { github, context, core } = createMocks({ apiUser: 'api-user' });
     const result = await checkTeamMembership({ github, context, core, ...BASE_OPTS });