diff --git a/erpnext/accounts/doctype/sales_invoice/sales_invoice.py b/erpnext/accounts/doctype/sales_invoice/sales_invoice.py
index 06e1e58..993ee5c 100644
--- a/erpnext/accounts/doctype/sales_invoice/sales_invoice.py
+++ b/erpnext/accounts/doctype/sales_invoice/sales_invoice.py
@@ -1166,6 +1166,9 @@
 		self.set_missing_values(for_validate = True)
 
 def validate_inter_company_party(doctype, party, company, inter_company_reference):
+	if not party:
+		return
+
 	if doctype in ["Sales Invoice", "Sales Order"]:
 		partytype, ref_partytype, internal = "Customer", "Supplier", "is_internal_customer"