diff --git a/erpnext/hr/doctype/employee/employee.py b/erpnext/hr/doctype/employee/employee.py
index cb0ce11..a2bb10c 100644
--- a/erpnext/hr/doctype/employee/employee.py
+++ b/erpnext/hr/doctype/employee/employee.py
@@ -45,6 +45,10 @@
 		if self.user_id:
 			self.validate_for_enabled_user_id()
 			self.validate_duplicate_user_id()
+		else:
+			existing_user_id = frappe.db.get_value("Employee", self.name, "user_id")
+			if existing_user_id:
+				frappe.permissions.remove_user_permission("Employee", self.name, existing_user_id)
 
 	def on_update(self):
 		if self.user_id: