diff --git a/erpnext/accounts/doctype/accounts_settings/accounts_settings.json b/erpnext/accounts/doctype/accounts_settings/accounts_settings.json
index 9ef011b9432..231c8ab8740 100644
--- a/erpnext/accounts/doctype/accounts_settings/accounts_settings.json
+++ b/erpnext/accounts/doctype/accounts_settings/accounts_settings.json
@@ -4,6 +4,13 @@
  "docstatus": 0, 
  "doctype": "DocType", 
  "fields": [
+  {
+   "fieldname": "check_supplier_invoice_uniqueness", 
+   "fieldtype": "Check", 
+   "label": "Check Supplier Invoice Number Uniqueness", 
+   "permlevel": 0, 
+   "precision": ""
+  }, 
   {
    "default": "1", 
    "description": "If enabled, the system will post accounting entries for inventory automatically.", 
@@ -43,7 +50,7 @@
  "icon": "icon-cog", 
  "idx": 1, 
  "issingle": 1, 
- "modified": "2015-02-05 05:11:34.163902", 
+ "modified": "2015-06-11 06:06:34.047890", 
  "modified_by": "Administrator", 
  "module": "Accounts", 
  "name": "Accounts Settings", 
diff --git a/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py b/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py
index c0ebf686cbc..2516ded589e 100644
--- a/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py
+++ b/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py
@@ -39,6 +39,7 @@ class PurchaseInvoice(BuyingController):
 
 		self.po_required()
 		self.pr_required()
+		self.validate_supplier_invoice()
 		self.check_active_purchase_items()
 		self.check_conversion_rate()
 		self.validate_credit_to_acc()
@@ -385,6 +386,16 @@ class PurchaseInvoice(BuyingController):
 				project.update_purchase_costing()
 				project.save()
 				project_list.append(d.project_name)
+				
+	def validate_supplier_invoice(self):
+		if self.bill_date:
+			if self.bill_date > self.posting_date:
+				frappe.throw("Supplier Invoice Date cannot be greater than Posting Date")
+		if self.bill_no:
+			if cint(frappe.db.get_single_value("Accounts Settings", "check_supplier_invoice_uniqueness")):
+				pi = frappe.db.exists("Purchase Invoice", {"bill_no": self.bill_no, "fiscal_year": self.fiscal_year})
+				if pi:
+					frappe.throw("Supplier Invoice No exists in Purchase Invoice {0}".format(pi))
 
 @frappe.whitelist()
 def get_expense_account(doctype, txt, searchfield, start, page_len, filters):