diff --git a/netbox/extras/models.py b/netbox/extras/models.py
index 9e6624fc4..da96d000e 100644
--- a/netbox/extras/models.py
+++ b/netbox/extras/models.py
@@ -100,7 +100,7 @@ class CustomField(models.Model):
         """
         Convert a string into the object it represents depending on the type of field
         """
-        if serialized_value is '':
+        if serialized_value == '':
             return None
         if self.type == CF_TYPE_INTEGER:
             return int(serialized_value)