diff --git a/django/db/backends/util.py b/django/db/backends/util.py
index 18f120b600..81c752e664 100644
--- a/django/db/backends/util.py
+++ b/django/db/backends/util.py
@@ -91,7 +91,7 @@ def typecast_boolean(s):
     return str(s)[0].lower() == 't'
 
 def typecast_decimal(s):
-    if s is None:
+    if s is None or s == '':
         return None
     return decimal.Decimal(s)