diff --git a/erpnext/buying/doctype/request_for_quotation/request_for_quotation.py b/erpnext/buying/doctype/request_for_quotation/request_for_quotation.py
index 8ea415d..6b39982 100644
--- a/erpnext/buying/doctype/request_for_quotation/request_for_quotation.py
+++ b/erpnext/buying/doctype/request_for_quotation/request_for_quotation.py
@@ -205,7 +205,7 @@
 		if preview:
 			return {"message": message, "subject": subject}
 
-		attachments = None
+		attachments = []
 		if self.send_attached_files:
 			attachments = self.get_attachments()