diff --git a/frappe/database/query.py b/frappe/database/query.py
index 587378b32f..15ab85ff56 100644
--- a/frappe/database/query.py
+++ b/frappe/database/query.py
@@ -244,7 +244,13 @@ class Query:
 					_operator = OPERATOR_MAP[value[0]]
 					conditions = conditions.where(_operator(Field(key), value[1]))
 			else:
-				conditions = conditions.where(_operator(Field(key), value))
+				if value is not None:
+					conditions = conditions.where(_operator(Field(key), value))
+				else:
+					_table = conditions._from[0]
+					field = getattr(_table, key)
+					conditions = conditions.where(field.isnull())
+
 		conditions = self.add_conditions(conditions, **kwargs)
 		return conditions
 
diff --git a/frappe/tests/test_db_query.py b/frappe/tests/test_db_query.py
index 5cd6690209..a53134064e 100644
--- a/frappe/tests/test_db_query.py
+++ b/frappe/tests/test_db_query.py
@@ -97,6 +97,12 @@ class TestReportview(unittest.TestCase):
 			self.assertFalse(result
 				in DatabaseQuery("DocType").execute(filters={"name": ["not in", 'DocType,DocField']}))
 
+	def test_none_filter(self):
+		query = frappe.db.query.get_sql("DocType", fields="name", filters={"restrict_to_domain": None})
+		sql = str(query).replace('`', '').replace('"', '')
+		condition = 'restrict_to_domain IS NULL'
+		self.assertIn(condition, sql)
+
 	def test_or_filters(self):
 		data = DatabaseQuery("DocField").execute(
 				filters={"parent": "DocType"}, fields=["fieldname", "fieldtype"],
@@ -149,7 +155,6 @@ class TestReportview(unittest.TestCase):
 			filters={"creation": ["between", ["2016-07-06", "2016-07-07"]]},
 			fields=["name"])
 
-
 	def test_ignore_permissions_for_get_filters_cond(self):
 		frappe.set_user('test2@example.com')
 		self.assertRaises(frappe.PermissionError, get_filters_cond, 'DocType', dict(istable=1), [])
@@ -351,7 +356,6 @@ class TestReportview(unittest.TestCase):
 		self.assertTrue(len(data) == 0)
 		self.assertTrue(len(frappe.get_all('Nested DocType', {'name': ('not ancestors of', 'Root')})) == len(frappe.get_all('Nested DocType')))
 
-
 	def test_is_set_is_not_set(self):
 		res = DatabaseQuery('DocType').execute(filters={'autoname': ['is', 'not set']})
 		self.assertTrue({'name': 'Integration Request'} in res)