diff --git a/odoo/addons/base/i18n/base.pot b/odoo/addons/base/i18n/base.pot
index 837ad5bde12..91daff7948e 100644
--- a/odoo/addons/base/i18n/base.pot
+++ b/odoo/addons/base/i18n/base.pot
@@ -30976,6 +30976,13 @@ msgstr ""
 msgid "You can not create recursive tags."
 msgstr ""
 
+#. module: base
+#. odoo-python
+#: code:addons/base/models/res_users.py:0
+#, python-format
+msgid "Deleting the template users is not allowed. Deleting this profile will compromise critical functionalities."
+msgstr ""
+
 #. module: base
 #: model:ir.model.constraint,message:base.constraint_res_users_login_key
 msgid "You can not have two users with the same login!"
diff --git a/odoo/addons/base/models/res_users.py b/odoo/addons/base/models/res_users.py
index 5c78215311c..4bd88c1dce8 100644
--- a/odoo/addons/base/models/res_users.py
+++ b/odoo/addons/base/models/res_users.py
@@ -661,10 +661,14 @@ class Users(models.Model):
         return res
 
     @api.ondelete(at_uninstall=True)
-    def _unlink_except_superuser(self):
+    def _unlink_except_master_data(self):
+        portal_user_template = self.env.ref('base.template_portal_user_id', False)
+        default_user_template = self.env.ref('base.default_user', False)
         if SUPERUSER_ID in self.ids:
             raise UserError(_('You can not remove the admin user as it is used internally for resources created by Odoo (updates, module installation, ...)'))
         self.clear_caches()
+        if (portal_user_template and portal_user_template in self) or (default_user_template and default_user_template in self):
+            raise UserError(_('Deleting the template users is not allowed. Deleting this profile will compromise critical functionalities.'))
 
     @api.model
     def _name_search(self, name, domain=None, operator='ilike', limit=None, order=None):