diff --git a/erpnext/utilities/transaction_base.py b/erpnext/utilities/transaction_base.py
index b7283529772..7e40fd681eb 100644
--- a/erpnext/utilities/transaction_base.py
+++ b/erpnext/utilities/transaction_base.py
@@ -65,7 +65,7 @@ class TransactionBase(StatusUpdater):
 					frappe.throw(_("Invalid reference {0} {1}").format(reference_doctype, reference_name))
 
 				for field, condition in fields:
-					if prevdoc_values[field] is not None and field not in self.exclude_fields:
+					if prevdoc_values[field] not in [None, ""] and field not in self.exclude_fields:
 						self.validate_value(field, condition, prevdoc_values[field], doc)
 
 	def get_prev_doc_reference_details(self, reference_names, reference_doctype, fields):