diff --git a/erpnext/accounts/report/financial_statements.py b/erpnext/accounts/report/financial_statements.py
index 39ff804518..f5309cd6fd 100644
--- a/erpnext/accounts/report/financial_statements.py
+++ b/erpnext/accounts/report/financial_statements.py
@@ -339,7 +339,7 @@ def sort_accounts(accounts, is_root=False, key="name"):
 	"""Sort root types as Asset, Liability, Equity, Income, Expense"""
 
 	def compare_accounts(a, b):
-		if re.split('\W+', a[key])[0].isdigit():
+		if re.split(r'\W+', a[key])[0].isdigit():
 			# if chart of accounts is numbered, then sort by number
 			return cmp(a[key], b[key])
 		elif is_root:
diff --git a/erpnext/erpnext_integrations/doctype/amazon_mws_settings/xml_utils.py b/erpnext/erpnext_integrations/doctype/amazon_mws_settings/xml_utils.py
index 99ede8f31d..52ba0239bb 100644
--- a/erpnext/erpnext_integrations/doctype/amazon_mws_settings/xml_utils.py
+++ b/erpnext/erpnext_integrations/doctype/amazon_mws_settings/xml_utils.py
@@ -88,7 +88,7 @@ class xml2dict(object):
 		ns = http://cs.sfsu.edu/csc867/myscheduler
 		name = patients
 		"""
-		result = re.compile("\{(.*)\}(.*)").search(tag)
+		result = re.compile(r"\{(.*)\}(.*)").search(tag)
 		if result:
 			value.namespace, tag = result.groups()
 
diff --git a/erpnext/regional/report/eway_bill/eway_bill.py b/erpnext/regional/report/eway_bill/eway_bill.py
index 4f777fcf7e..09d5f79167 100644
--- a/erpnext/regional/report/eway_bill/eway_bill.py
+++ b/erpnext/regional/report/eway_bill/eway_bill.py
@@ -41,7 +41,7 @@ def get_data(filters):
 	}
 
 	# Regular expression set to remove all the special characters
-	special_characters = "[$%^*()+\\[\]{};':\"\\|<>.?]"
+	special_characters = r"[$%^*()+\\[\]{};':\"\\|<>.?]"
 
 	for row in data:
 		set_defaults(row)
diff --git a/erpnext/regional/report/fichier_des_ecritures_comptables_[fec]/fichier_des_ecritures_comptables_[fec].py b/erpnext/regional/report/fichier_des_ecritures_comptables_[fec]/fichier_des_ecritures_comptables_[fec].py
index e903c9f00a..697058def5 100644
--- a/erpnext/regional/report/fichier_des_ecritures_comptables_[fec]/fichier_des_ecritures_comptables_[fec].py
+++ b/erpnext/regional/report/fichier_des_ecritures_comptables_[fec]/fichier_des_ecritures_comptables_[fec].py
@@ -116,7 +116,7 @@ def get_result_as_list(data, filters):
 		if d.get("voucher_no").startswith("{0}-".format(JournalCode)) or d.get("voucher_no").startswith("{0}/".format(JournalCode)):
 			EcritureNum = re.split("-|/", d.get("voucher_no"))[1]
 		else:
-			EcritureNum = re.search("{0}(\d+)".format(JournalCode), d.get("voucher_no"), re.IGNORECASE).group(1)
+			EcritureNum = re.search(r"{0}(\d+)".format(JournalCode), d.get("voucher_no"), re.IGNORECASE).group(1)
 
 		EcritureDate = format_datetime(d.get("GlPostDate"), "yyyyMMdd")
 
diff --git a/erpnext/setup/doctype/naming_series/naming_series.py b/erpnext/setup/doctype/naming_series/naming_series.py
index c1f9433b41..c5d5747961 100644
--- a/erpnext/setup/doctype/naming_series/naming_series.py
+++ b/erpnext/setup/doctype/naming_series/naming_series.py
@@ -79,7 +79,8 @@ class NamingSeries(Document):
 		options = self.scrub_options_list(ol)
 
 		# validate names
-		for i in options: self.validate_series_name(i)
+		for i in options:
+			self.validate_series_name(i)
 
 		if options and self.user_must_always_select:
 			options = [''] + options
@@ -138,7 +139,7 @@ class NamingSeries(Document):
 
 	def validate_series_name(self, n):
 		import re
-		if not re.match("^[\w\- /.#{}]*$", n, re.UNICODE):
+		if not re.match(r"^[\w\- \/.#{}]+$", n, re.UNICODE):
 			throw(_('Special Characters except "-", "#", ".", "/", "{" and "}" not allowed in naming series'))
 
 	@frappe.whitelist()