diff --git a/addons/hr_holidays/tests/__init__.py b/addons/hr_holidays/tests/__init__.py
index f983d595fc5..da196a0ade6 100644
--- a/addons/hr_holidays/tests/__init__.py
+++ b/addons/hr_holidays/tests/__init__.py
@@ -16,3 +16,4 @@ from . import test_company_leave
 from . import test_res_partner
 from . import test_stress_days
 from . import test_global_leaves
+from . import test_uninstall
diff --git a/addons/hr_holidays/tests/test_uninstall.py b/addons/hr_holidays/tests/test_uninstall.py
new file mode 100644
index 00000000000..461e1ab7e21
--- /dev/null
+++ b/addons/hr_holidays/tests/test_uninstall.py
@@ -0,0 +1,28 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo.addons.base.models.ir_model import MODULE_UNINSTALL_FLAG
+from odoo.tests import tagged, TransactionCase
+
+
+@tagged('-at_install', 'post_install')
+class TestHrLeaveUninstall(TransactionCase):
+    def test_unlink_model(self):
+        model = self.env['ir.model'].search([('model', '=', 'hr.leave')])
+        activity_type = self.env['mail.activity'].search([
+            ('res_model', '=', 'hr.leave')
+        ]).activity_type_id
+
+        self.assertTrue(activity_type)
+        self.assertIn('hr.leave', activity_type.mapped('res_model'))
+
+        model.sudo().with_context(**{MODULE_UNINSTALL_FLAG: True}).unlink()
+        self.assertFalse(model.exists())
+
+        domain = [('res_model', '=', 'hr.leave')]
+        self.assertFalse(self.env['mail.activity'].search(domain))
+        self.assertFalse(self.env['mail.activity.type'].search(domain))
+        self.assertFalse(self.env['mail.followers'].search(domain))
+        self.assertFalse(self.env['mail.message'].search([
+            ('model', '=', 'hr.leave'),
+        ]))
diff --git a/addons/mail/models/ir_model.py b/addons/mail/models/ir_model.py
index d763849132b..55e62cc9ebe 100644
--- a/addons/mail/models/ir_model.py
+++ b/addons/mail/models/ir_model.py
@@ -22,6 +22,10 @@ class IrModel(models.Model):
     def unlink(self):
         # Delete followers, messages and attachments for models that will be unlinked.
         models = tuple(self.mapped('model'))
+        model_ids = tuple(self.ids)
+
+        query = "DELETE FROM mail_activity WHERE res_model_id IN %s"
+        self.env.cr.execute(query, [model_ids])
 
         query = "DELETE FROM mail_activity_type WHERE res_model IN %s"
         self.env.cr.execute(query, [models])
diff --git a/addons/mail/tests/__init__.py b/addons/mail/tests/__init__.py
index eaf51ea9ab6..4f050f4c3cd 100644
--- a/addons/mail/tests/__init__.py
+++ b/addons/mail/tests/__init__.py
@@ -14,4 +14,5 @@ from . import test_res_partner
 from . import test_res_users
 from . import test_res_users_settings
 from . import test_rtc
+from . import test_uninstall
 from . import test_update_notification
diff --git a/addons/mail/tests/test_uninstall.py b/addons/mail/tests/test_uninstall.py
new file mode 100644
index 00000000000..07a59a4ca97
--- /dev/null
+++ b/addons/mail/tests/test_uninstall.py
@@ -0,0 +1,31 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo.tests import tagged, TransactionCase
+
+
+@tagged('-at_install', 'post_install')
+class TestMailUninstall(TransactionCase):
+    def test_unlink_model(self):
+        model = self.env['ir.model'].create({
+            'name': 'Test Model',
+            'model': 'x_test_model',
+            'state': 'manual',
+            'is_mail_thread': True,
+        })
+        activity_type = self.env['mail.activity.type'].create({
+            'name': 'Test Activity Type',
+            'res_model': model.model,
+        })
+        record = self.env[model.model].create({})
+
+        activity = self.env['mail.activity'].create({
+            'activity_type_id': activity_type.id,
+            'res_model_id': model.id,
+            'res_id': record.id,
+        })
+
+        model.unlink()
+        self.assertFalse(model.exists())
+        self.assertFalse(activity_type.exists())
+        self.assertFalse(activity.exists())