diff --git a/erpnext/crm/doctype/appointment/appointment.py b/erpnext/crm/doctype/appointment/appointment.py
index 714e88d..2b9d31d 100644
--- a/erpnext/crm/doctype/appointment/appointment.py
+++ b/erpnext/crm/doctype/appointment/appointment.py
@@ -142,6 +142,8 @@
                 'party_name': self.lead,
             },
             order_by='creation desc')
+        if not opporutnities:
+            return None
         latest_opportunity = frappe.get_doc(
             'Opportunity', opporutnities[0].name)
         assignee = latest_opportunity._assign