diff --git a/erpnext/controllers/accounts_controller.py b/erpnext/controllers/accounts_controller.py
index 847e09e..aba7a88 100644
--- a/erpnext/controllers/accounts_controller.py
+++ b/erpnext/controllers/accounts_controller.py
@@ -424,8 +424,7 @@
 
 	def get_stock_items(self):
 		stock_items = []
-		item_codes = list(set(item.item_code for item in
-			self.get(self.fname)))
+		item_codes = list(set(item.item_code for item in self.get(self.fname)))
 		if item_codes:
 			stock_items = [r[0] for r in frappe.db.sql("""select name
 				from `tabItem` where name in (%s) and is_stock_item='Yes'""" % \
diff --git a/erpnext/controllers/stock_controller.py b/erpnext/controllers/stock_controller.py
index d310347..83cec98 100644
--- a/erpnext/controllers/stock_controller.py
+++ b/erpnext/controllers/stock_controller.py
@@ -275,6 +275,16 @@
 			and voucher_no=%s""", (self.doctype, self.name)):
 				self.make_gl_entries()
 
+	def get_serialized_items(self):
+		serialized_items = []
+		item_codes = list(set([d.item_code for d in self.get(self.fname)]))
+		if item_codes:
+			serialized_items = frappe.db.sql_list("""select name from `tabItem`
+				where has_serial_no='Yes' and name in ({})""".format(", ".join(["%s"]*len(item_codes))),
+				tuple(item_codes))
+
+		return serialized_items
+
 def update_gl_entries_after(posting_date, posting_time, warehouse_account=None, for_items=None):
 	def _delete_gl_entries(voucher_type, voucher_no):
 		frappe.db.sql("""delete from `tabGL Entry`
diff --git a/erpnext/stock/doctype/stock_entry/stock_entry.py b/erpnext/stock/doctype/stock_entry/stock_entry.py
index 125a293..a7e007a 100644
--- a/erpnext/stock/doctype/stock_entry/stock_entry.py
+++ b/erpnext/stock/doctype/stock_entry/stock_entry.py
@@ -77,6 +77,7 @@
 
 	def validate_item(self):
 		stock_items = self.get_stock_items()
+		serialized_items = self.get_serialized_items()
 		for item in self.get("mtn_details"):
 			if item.item_code not in stock_items:
 				frappe.throw(_("{0} is not a stock Item").format(item.item_code))
@@ -88,6 +89,12 @@
 				item.conversion_factor = 1
 			if not item.transfer_qty:
 				item.transfer_qty = item.qty * item.conversion_factor
+			if (self.purpose in ("Material Transfer", "Sales Return", "Purchase Return")
+				and not item.serial_no
+				and item.item_code in serialized_items):
+				frappe.throw(_("Row #{0}: Please specify Serial No for Item {1}").format(item.idx, item.item_code),
+					frappe.MandatoryError)
+
 
 	def validate_warehouse(self, pro_obj):
 		"""perform various (sometimes conditional) validations on warehouse"""