diff --git a/integrationExamples/gpt/userId_example.html b/integrationExamples/gpt/userId_example.html
index 4ed32270be7..48b349649bc 100644
--- a/integrationExamples/gpt/userId_example.html
+++ b/integrationExamples/gpt/userId_example.html
@@ -260,6 +260,9 @@
             },
             {
               "name": "dacId"
+            },
+            {
+              "name": "gravitompId"
             }
           ],
           "syncDelay": 5000,
diff --git a/modules/.submodules.json b/modules/.submodules.json
index 54bf77c7dca..bf836331bca 100644
--- a/modules/.submodules.json
+++ b/modules/.submodules.json
@@ -41,7 +41,8 @@
     "unifiedIdSystem",
     "verizonMediaIdSystem",
     "zeotapIdPlusIdSystem",
-    "adqueryIdSystem"
+    "adqueryIdSystem", 
+    "gravitoIdSystem"
   ],
   "adpod": [
     "freeWheelAdserverVideo",
diff --git a/modules/gravitoIdSystem.js b/modules/gravitoIdSystem.js
new file mode 100644
index 00000000000..30fa3abd6d2
--- /dev/null
+++ b/modules/gravitoIdSystem.js
@@ -0,0 +1,57 @@
+/**
+ * This module adds gravitompId to the User ID module
+ * The {@link module:modules/userId} module is required
+ * @module modules/gravitoIdSystem
+ * @requires module:modules/userId
+ */
+
+import { submodule } from '../src/hook.js';
+import { getStorageManager } from '../src/storageManager.js';
+
+export const storage = getStorageManager();
+
+export const cookieKey = 'gravitompId';
+
+export const gravitoIdSystemSubmodule = {
+  /**
+  * used to link submodule with config
+  * @type {string}
+  */
+  name: 'gravitompId',
+
+  /**
+  * performs action to obtain id
+  * @function
+  * @returns { {id: {gravitompId: string}} | undefined }
+  */
+  getId: function() {
+    const newId = storage.getCookie(cookieKey);
+    if (!newId) {
+      return undefined;
+    }
+    const result = {
+      gravitompId: newId
+    }
+    return {id: result};
+  },
+
+  /**
+  * decode the stored id value for passing to bid requests
+  * @function
+  * @param { {gravitompId: string} } value
+  * @returns { {gravitompId: {id: string} } | undefined }
+  */
+  decode: function(value) {
+    if (value && typeof value === 'object') {
+      const result = {};
+      if (value.gravitompId) {
+        result.id = value.gravitompId
+      }
+      return {gravitompId: result};
+    }
+    return undefined;
+  },
+
+}
+
+submodule('userId', gravitoIdSystemSubmodule);
diff --git a/modules/gravitoIdSystem.md b/modules/gravitoIdSystem.md
new file mode 100644
index 00000000000..af4946779c5
--- /dev/null
+++ b/modules/gravitoIdSystem.md
@@ -0,0 +1,28 @@
+## Gravito User ID Submodule
+
+Gravito ID, provided by [Gravito Ltd.](https://gravito.net), is ID for ad targeting by using 1st party cookie.
+Please contact Gravito Ltd. before using this ID.
+
+## Building Prebid with Gravito ID Support
+
+First, make sure to add the Gravito ID submodule to your Prebid.js package with:
+
+```
+gulp build --modules=gravitoIdSystem
+```
+
+The following configuration parameters are available:
+
+```javascript
+pbjs.setConfig({
+    userSync: {
+        userIds: [{
+            name: 'gravitompId'
+        }]
+    }
+});
+```
+
+| Param under userSync.userIds[] | Scope | Type | Description | Example |
+| --- | --- | --- | --- | --- |
+| name | Required | String | The name of this module. | `"gravitompId"` |
diff --git a/modules/userId/eids.js b/modules/userId/eids.js
index 15fefb5619c..8176fa9f4d2 100644
--- a/modules/userId/eids.js
+++ b/modules/userId/eids.js
@@ -308,6 +308,12 @@ export const USER_IDS_CONFIG = {
       return data.envelope;
     }
   },
+
+  // Gravito MP ID
+  'gravitompId': {
+    source: 'gravito.net',
+    atype: 1
+  },
 };
 
 // this function will create an eid object for the given UserId sub-module
diff --git a/modules/userId/userId.md b/modules/userId/userId.md
index 38b196a3b4b..22af69ce1e3 100644
--- a/modules/userId/userId.md
+++ b/modules/userId/userId.md
@@ -161,6 +161,9 @@ pbjs.setConfig({
                   },
         {
              name: "dacId"
+        }, 
+        {
+            name: "gravitompId"
         }
         ],
         syncDelay: 5000,
diff --git a/test/spec/modules/gravitoIdSystem_spec.js b/test/spec/modules/gravitoIdSystem_spec.js
new file mode 100644
index 00000000000..e904355f7f1
--- /dev/null
+++ b/test/spec/modules/gravitoIdSystem_spec.js
@@ -0,0 +1,51 @@
+import { gravitoIdSystemSubmodule, storage, cookieKey } from 'modules/gravitoIdSystem.js';
+
+const GRAVITOID_TEST_VALUE = 'gravitompIdTest';
+const GRAVITOID_TEST_OBJ = {
+  gravitompId: GRAVITOID_TEST_VALUE
+};
+
+describe('gravitompId module', function () {
+  let getCookieStub;
+
+  beforeEach(function (done) {
+    getCookieStub = sinon.stub(storage, 'getCookie');
+    done();
+  });
+
+  afterEach(function () {
+    getCookieStub.restore();
+  });
+
+  const cookieTestCasesForEmpty = [
+    undefined,
+    null,
+    ''
+  ]
+
+  describe('getId()', function () {
+    it('should return the gravitompId when it exists in cookie', function () {
+      getCookieStub.withArgs(cookieKey).returns(GRAVITOID_TEST_VALUE);
+      const id = gravitoIdSystemSubmodule.getId();
+      expect(id).to.be.deep.equal({id: {gravitompId: GRAVITOID_TEST_VALUE}});
+    });
+
+    cookieTestCasesForEmpty.forEach(testCase => it('should return the gravitompId when it not exists in cookie', function () {
+      getCookieStub.withArgs(cookieKey).returns(testCase);
+      const id = gravitoIdSystemSubmodule.getId();
+      expect(id).to.be.deep.equal(undefined);
+    }));
+  });
+
+  describe('decode()', function () {
+    it('should return the gravitompId when it exists in cookie', function () {
+      const decoded = gravitoIdSystemSubmodule.decode(GRAVITOID_TEST_OBJ);
+      expect(decoded).to.be.deep.equal({gravitompId: {id: GRAVITOID_TEST_VALUE}});
+    });
+
+    it('should return the undefined when decode id is not "string"', function () {
+      const decoded = gravitoIdSystemSubmodule.decode(1);
+      expect(decoded).to.equal(undefined);
+    });
+  });
+});