diff --git a/erpnext/controllers/taxes_and_totals.py b/erpnext/controllers/taxes_and_totals.py
index 52190765c9..d2a913c74b 100644
--- a/erpnext/controllers/taxes_and_totals.py
+++ b/erpnext/controllers/taxes_and_totals.py
@@ -116,11 +116,11 @@ class calculate_taxes_and_totals(object):
 				if item.discount_percentage == 100:
 					item.rate = 0.0
 				elif item.price_list_rate:
-					if item.pricing_rules or item.discount_percentage > 0:
+					if item.pricing_rules or abs(item.discount_percentage) > 0:
 						item.rate = flt(item.price_list_rate *
 							(1.0 - (item.discount_percentage / 100.0)), item.precision("rate"))
 						item.discount_amount = item.price_list_rate * (item.discount_percentage / 100.0)
-					elif item.discount_amount and item.pricing_rules:
+					elif item.discount_amount or item.pricing_rules:
 						item.rate =  item.price_list_rate - item.discount_amount
 
 				if item.doctype in ['Quotation Item', 'Sales Order Item', 'Delivery Note Item', 'Sales Invoice Item', 'POS Invoice Item', 'Purchase Invoice Item', 'Purchase Order Item', 'Purchase Receipt Item']: