diff --git a/erpnext/selling/report/item_wise_sales_history/item_wise_sales_history.py b/erpnext/selling/report/item_wise_sales_history/item_wise_sales_history.py
index 1bc4657..0a70b97 100644
--- a/erpnext/selling/report/item_wise_sales_history/item_wise_sales_history.py
+++ b/erpnext/selling/report/item_wise_sales_history/item_wise_sales_history.py
@@ -191,7 +191,7 @@
 		conditions += "AND so_item.item_code = '%s'" %frappe.db.escape(filters.item_code)
 
 	if filters.get("customer"):
-		conditions += "AND so.customer = '%s'" %frappe.db.escape(filters.customer)
+		conditions += "AND so.customer = %s" %frappe.db.escape(filters.customer)
 
 	return conditions