diff --git a/__tests__/fixtures/event_pull_request_target.env b/__tests__/fixtures/event_pull_request_target.env
new file mode 100644
index 0000000..b13a20b
--- /dev/null
+++ b/__tests__/fixtures/event_pull_request_target.env
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+GITHUB_ACTION_REPOSITORY=
+GITHUB_ACTOR=crazy-max
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+GITHUB_BASE_REF=master
+GITHUB_ENV=/home/runner/work/_temp/_runner_file_commands/set_env_cc4da131-0660-4771-8663-0f96c0fc944f
+GITHUB_EVENT_NAME=pull_request_target
+GITHUB_EVENT_PATH=./__tests__/fixtures/event_pull_request_target.json
+GITHUB_GRAPHQL_URL=https://api.github.com/graphql
+GITHUB_HEAD_REF=test-pr-target
+GITHUB_JOB=build
+GITHUB_PATH=/home/runner/work/_temp/_runner_file_commands/add_path_cc4da131-0660-4771-8663-0f96c0fc944f
+GITHUB_REF=refs/heads/master
+GITHUB_REPOSITORY=crazy-max/test-docker-action
+GITHUB_REPOSITORY_OWNER=crazy-max
+GITHUB_RETENTION_DAYS=90
+GITHUB_RUN_ID=867725119
+GITHUB_RUN_NUMBER=12
+GITHUB_SERVER_URL=https://github.com
+GITHUB_SHA=f24900bfcfee76d8055c8421a164c7e57ad20e68
+GITHUB_WORKFLOW=push-ghcr
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diff --git a/__tests__/fixtures/event_pull_request_target.json b/__tests__/fixtures/event_pull_request_target.json
new file mode 100644
index 0000000..0ca97c9
--- /dev/null
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+    "user": {
+      "avatar_url": "https://avatars.githubusercontent.com/u/1951866?v=4",
+      "events_url": "https://api.github.com/users/crazy-max/events{/privacy}",
+      "followers_url": "https://api.github.com/users/crazy-max/followers",
+      "following_url": "https://api.github.com/users/crazy-max/following{/other_user}",
+      "gists_url": "https://api.github.com/users/crazy-max/gists{/gist_id}",
+      "gravatar_id": "",
+      "html_url": "https://github.com/crazy-max",
+      "id": 1951866,
+      "login": "crazy-max",
+      "node_id": "MDQ6VXNlcjE5NTE4NjY=",
+      "organizations_url": "https://api.github.com/users/crazy-max/orgs",
+      "received_events_url": "https://api.github.com/users/crazy-max/received_events",
+      "repos_url": "https://api.github.com/users/crazy-max/repos",
+      "site_admin": false,
+      "starred_url": "https://api.github.com/users/crazy-max/starred{/owner}{/repo}",
+      "subscriptions_url": "https://api.github.com/users/crazy-max/subscriptions",
+      "type": "User",
+      "url": "https://api.github.com/users/crazy-max"
+    }
+  },
+  "repository": {
+    "archive_url": "https://api.github.com/repos/crazy-max/test-docker-action/{archive_format}{/ref}",
+    "archived": false,
+    "assignees_url": "https://api.github.com/repos/crazy-max/test-docker-action/assignees{/user}",
+    "blobs_url": "https://api.github.com/repos/crazy-max/test-docker-action/git/blobs{/sha}",
+    "branches_url": "https://api.github.com/repos/crazy-max/test-docker-action/branches{/branch}",
+    "clone_url": "https://github.com/crazy-max/test-docker-action.git",
+    "collaborators_url": "https://api.github.com/repos/crazy-max/test-docker-action/collaborators{/collaborator}",
+    "comments_url": "https://api.github.com/repos/crazy-max/test-docker-action/comments{/number}",
+    "commits_url": "https://api.github.com/repos/crazy-max/test-docker-action/commits{/sha}",
+    "compare_url": "https://api.github.com/repos/crazy-max/test-docker-action/compare/{base}...{head}",
+    "contents_url": "https://api.github.com/repos/crazy-max/test-docker-action/contents/{+path}",
+    "contributors_url": "https://api.github.com/repos/crazy-max/test-docker-action/contributors",
+    "created_at": "2020-08-07T09:23:00Z",
+    "default_branch": "master",
+    "deployments_url": "https://api.github.com/repos/crazy-max/test-docker-action/deployments",
+    "description": "Test \"Docker\" Actions",
+    "disabled": false,
+    "downloads_url": "https://api.github.com/repos/crazy-max/test-docker-action/downloads",
+    "events_url": "https://api.github.com/repos/crazy-max/test-docker-action/events",
+    "fork": false,
+    "forks": 4,
+    "forks_count": 4,
+    "forks_url": "https://api.github.com/repos/crazy-max/test-docker-action/forks",
+    "full_name": "crazy-max/test-docker-action",
+    "git_commits_url": "https://api.github.com/repos/crazy-max/test-docker-action/git/commits{/sha}",
+    "git_refs_url": "https://api.github.com/repos/crazy-max/test-docker-action/git/refs{/sha}",
+    "git_tags_url": "https://api.github.com/repos/crazy-max/test-docker-action/git/tags{/sha}",
+    "git_url": "git://github.com/crazy-max/test-docker-action.git",
+    "has_downloads": true,
+    "has_issues": false,
+    "has_pages": false,
+    "has_projects": false,
+    "has_wiki": false,
+    "homepage": "",
+    "hooks_url": "https://api.github.com/repos/crazy-max/test-docker-action/hooks",
+    "html_url": "https://github.com/crazy-max/test-docker-action",
+    "id": 285789493,
+    "issue_comment_url": "https://api.github.com/repos/crazy-max/test-docker-action/issues/comments{/number}",
+    "issue_events_url": "https://api.github.com/repos/crazy-max/test-docker-action/issues/events{/number}",
+    "issues_url": "https://api.github.com/repos/crazy-max/test-docker-action/issues{/number}",
+    "keys_url": "https://api.github.com/repos/crazy-max/test-docker-action/keys{/key_id}",
+    "labels_url": "https://api.github.com/repos/crazy-max/test-docker-action/labels{/name}",
+    "language": "Dockerfile",
+    "languages_url": "https://api.github.com/repos/crazy-max/test-docker-action/languages",
+    "license": {
+      "key": "mit",
+      "name": "MIT License",
+      "node_id": "MDc6TGljZW5zZTEz",
+      "spdx_id": "MIT",
+      "url": "https://api.github.com/licenses/mit"
+    },
+    "merges_url": "https://api.github.com/repos/crazy-max/test-docker-action/merges",
+    "milestones_url": "https://api.github.com/repos/crazy-max/test-docker-action/milestones{/number}",
+    "mirror_url": null,
+    "name": "test-docker-action",
+    "node_id": "MDEwOlJlcG9zaXRvcnkyODU3ODk0OTM=",
+    "notifications_url": "https://api.github.com/repos/crazy-max/test-docker-action/notifications{?since,all,participating}",
+    "open_issues": 4,
+    "open_issues_count": 4,
+    "owner": {
+      "avatar_url": "https://avatars.githubusercontent.com/u/1951866?v=4",
+      "events_url": "https://api.github.com/users/crazy-max/events{/privacy}",
+      "followers_url": "https://api.github.com/users/crazy-max/followers",
+      "following_url": "https://api.github.com/users/crazy-max/following{/other_user}",
+      "gists_url": "https://api.github.com/users/crazy-max/gists{/gist_id}",
+      "gravatar_id": "",
+      "html_url": "https://github.com/crazy-max",
+      "id": 1951866,
+      "login": "crazy-max",
+      "node_id": "MDQ6VXNlcjE5NTE4NjY=",
+      "organizations_url": "https://api.github.com/users/crazy-max/orgs",
+      "received_events_url": "https://api.github.com/users/crazy-max/received_events",
+      "repos_url": "https://api.github.com/users/crazy-max/repos",
+      "site_admin": false,
+      "starred_url": "https://api.github.com/users/crazy-max/starred{/owner}{/repo}",
+      "subscriptions_url": "https://api.github.com/users/crazy-max/subscriptions",
+      "type": "User",
+      "url": "https://api.github.com/users/crazy-max"
+    },
+    "private": false,
+    "pulls_url": "https://api.github.com/repos/crazy-max/test-docker-action/pulls{/number}",
+    "pushed_at": "2021-05-23T01:38:41Z",
+    "releases_url": "https://api.github.com/repos/crazy-max/test-docker-action/releases{/id}",
+    "size": 137,
+    "ssh_url": "git@github.com:crazy-max/test-docker-action.git",
+    "stargazers_count": 3,
+    "stargazers_url": "https://api.github.com/repos/crazy-max/test-docker-action/stargazers",
+    "statuses_url": "https://api.github.com/repos/crazy-max/test-docker-action/statuses/{sha}",
+    "subscribers_url": "https://api.github.com/repos/crazy-max/test-docker-action/subscribers",
+    "subscription_url": "https://api.github.com/repos/crazy-max/test-docker-action/subscription",
+    "svn_url": "https://github.com/crazy-max/test-docker-action",
+    "tags_url": "https://api.github.com/repos/crazy-max/test-docker-action/tags",
+    "teams_url": "https://api.github.com/repos/crazy-max/test-docker-action/teams",
+    "trees_url": "https://api.github.com/repos/crazy-max/test-docker-action/git/trees{/sha}",
+    "updated_at": "2021-05-23T01:37:33Z",
+    "url": "https://api.github.com/repos/crazy-max/test-docker-action",
+    "watchers": 3,
+    "watchers_count": 3
+  },
+  "sender": {
+    "avatar_url": "https://avatars.githubusercontent.com/u/1951866?v=4",
+    "events_url": "https://api.github.com/users/crazy-max/events{/privacy}",
+    "followers_url": "https://api.github.com/users/crazy-max/followers",
+    "following_url": "https://api.github.com/users/crazy-max/following{/other_user}",
+    "gists_url": "https://api.github.com/users/crazy-max/gists{/gist_id}",
+    "gravatar_id": "",
+    "html_url": "https://github.com/crazy-max",
+    "id": 1951866,
+    "login": "crazy-max",
+    "node_id": "MDQ6VXNlcjE5NTE4NjY=",
+    "organizations_url": "https://api.github.com/users/crazy-max/orgs",
+    "received_events_url": "https://api.github.com/users/crazy-max/received_events",
+    "repos_url": "https://api.github.com/users/crazy-max/repos",
+    "site_admin": false,
+    "starred_url": "https://api.github.com/users/crazy-max/starred{/owner}{/repo}",
+    "subscriptions_url": "https://api.github.com/users/crazy-max/subscriptions",
+    "type": "User",
+    "url": "https://api.github.com/users/crazy-max"
+  }
+}
diff --git a/__tests__/meta.test.ts b/__tests__/meta.test.ts
index fb4bc1d..c770f74 100644
--- a/__tests__/meta.test.ts
+++ b/__tests__/meta.test.ts
@@ -1776,6 +1776,71 @@ describe('pr', () => {
         "org.opencontainers.image.revision=1e9249f05bfc090e0688b8fb9c1b347586add504",
         "org.opencontainers.image.licenses=MIT"
       ]
+    ],
+    [
+      'pr07',
+      'event_pull_request_target.env',
+      {
+        images: ['org/app', 'ghcr.io/user/app'],
+        tags: [
+          `type=sha,priority=2000`,
+          `type=ref,event=pr`
+        ]
+      } as Inputs,
+      {
+        main: 'sha-f24900b',
+        partial: ['pr-8'],
+        latest: false
+      } as Version,
+      [
+        'org/app:sha-f24900b',
+        'org/app:pr-8',
+        'ghcr.io/user/app:sha-f24900b',
+        'ghcr.io/user/app:pr-8'
+      ],
+      [
+        "org.opencontainers.image.title=Hello-World",
+        "org.opencontainers.image.description=This your first repo!",
+        "org.opencontainers.image.url=https://github.com/octocat/Hello-World",
+        "org.opencontainers.image.source=https://github.com/octocat/Hello-World",
+        "org.opencontainers.image.version=sha-f24900b",
+        "org.opencontainers.image.created=2020-01-10T00:30:00.000Z",
+        "org.opencontainers.image.revision=f24900bfcfee76d8055c8421a164c7e57ad20e68",
+        "org.opencontainers.image.licenses=MIT"
+      ]
+    ],
+    [
+      'pr08',
+      'event_pull_request_target.env',
+      {
+        images: ['org/app', 'ghcr.io/user/app'],
+        tags: [
+          `type=ref,event=pr,prefix=`
+        ],
+        flavor: [
+          `prefix=glo-`,
+          `suffix=-bal`
+        ]
+      } as Inputs,
+      {
+        main: '8-bal',
+        partial: [],
+        latest: false
+      } as Version,
+      [
+        'org/app:8-bal',
+        'ghcr.io/user/app:8-bal'
+      ],
+      [
+        "org.opencontainers.image.title=Hello-World",
+        "org.opencontainers.image.description=This your first repo!",
+        "org.opencontainers.image.url=https://github.com/octocat/Hello-World",
+        "org.opencontainers.image.source=https://github.com/octocat/Hello-World",
+        "org.opencontainers.image.version=8-bal",
+        "org.opencontainers.image.created=2020-01-10T00:30:00.000Z",
+        "org.opencontainers.image.revision=f24900bfcfee76d8055c8421a164c7e57ad20e68",
+        "org.opencontainers.image.licenses=MIT"
+      ]
     ]
   ])('given %p with %p event', tagsLabelsTest);
 });
diff --git a/dist/index.js b/dist/index.js
index 3887e51..72c97bd 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -533,10 +533,14 @@ class Meta {
         return Meta.setVersion(version, vraw, this.flavor.latest == 'auto' ? true : this.flavor.latest == 'true');
     }
     procRefPr(version, tag) {
-        if (!/^refs\/pull\//.test(this.context.ref)) {
+        let ref = this.context.ref;
+        if (/pull_request_target/.test(this.context.eventName)) {
+            ref = `refs/pull/${this.context.payload.number}/merge`;
+        }
+        if (!/^refs\/pull\//.test(ref)) {
             return version;
         }
-        const vraw = this.setValue(this.context.ref.replace(/^refs\/pull\//g, '').replace(/\/merge$/g, ''), tag);
+        const vraw = this.setValue(ref.replace(/^refs\/pull\//g, '').replace(/\/merge$/g, ''), tag);
         return Meta.setVersion(version, vraw, this.flavor.latest == 'auto' ? false : this.flavor.latest == 'true');
     }
     procEdge(version, tag) {
diff --git a/src/meta.ts b/src/meta.ts
index b608f6e..d0e9201 100644
--- a/src/meta.ts
+++ b/src/meta.ts
@@ -191,10 +191,15 @@ export class Meta {
   }
 
   private procRefPr(version: Version, tag: tcl.Tag): Version {
-    if (!/^refs\/pull\//.test(this.context.ref)) {
+    let ref = this.context.ref;
+    if (/pull_request_target/.test(this.context.eventName)) {
+      ref = `refs/pull/${this.context.payload.number}/merge`;
+    }
+    if (!/^refs\/pull\//.test(ref)) {
       return version;
     }
-    const vraw = this.setValue(this.context.ref.replace(/^refs\/pull\//g, '').replace(/\/merge$/g, ''), tag);
+
+    const vraw = this.setValue(ref.replace(/^refs\/pull\//g, '').replace(/\/merge$/g, ''), tag);
     return Meta.setVersion(version, vraw, this.flavor.latest == 'auto' ? false : this.flavor.latest == 'true');
   }