diff --git a/addons/website/models/website.py b/addons/website/models/website.py
index a371d760e8e..0c18a2c05d9 100644
--- a/addons/website/models/website.py
+++ b/addons/website/models/website.py
@@ -1114,6 +1114,13 @@ class Menu(models.Model):
                 res = super(Menu, self).create(vals)
         return res  # Only one record is returned but multiple could have been created
 
+    @api.multi
+    def unlink(self):
+        default_menu = self.env.ref('website.main_menu', raise_if_not_found=False)
+        for menu in self.filtered(lambda m: default_menu and m.parent_id.id == default_menu.id):
+            self.env['website.menu'].search([('url', '=', menu.url), ('id', '!=', menu.id)]).unlink()
+        return super(Menu, self).unlink()
+
     @api.one
     def _compute_visible(self):
         visible = True
diff --git a/addons/website/tests/test_menu.py b/addons/website/tests/test_menu.py
index c907b986171..e2a80902aea 100644
--- a/addons/website/tests/test_menu.py
+++ b/addons/website/tests/test_menu.py
@@ -59,3 +59,11 @@ class TestMenu(common.TransactionCase):
         total_menus = Menu.search_count([])
         Website.create({'name': 'new website'})
         self.assertEqual(total_menus + 4, Menu.search_count([]), "New website's bootstraping should have duplicate default menu tree (Top/Home/Contactus/Sub Default Menu)")
+
+    def test_default_menu_unlink(self):
+        Menu = self.env['website.menu']
+        total_menu_items = Menu.search_count([])
+
+        default_menu = self.env.ref('website.main_menu')
+        default_menu.child_id[0].unlink()
+        self.assertEqual(total_menu_items - 3, Menu.search_count([]), "Deleting a default menu item should delete its 'copies' (same URL) from website's menu trees. In this case, the default child menu and its copies on website 1 and website 2")