diff --git a/smart_selects/encoders.py b/smart_selects/encoders.py
new file mode 100644
index 0000000..bec91f1
--- /dev/null
+++ b/smart_selects/encoders.py
@@ -0,0 +1,9 @@
+import json
+from uuid import UUID
+
+
+class UUIDEncoder(json.JSONEncoder):
+    def default(self, obj):
+        if isinstance(obj, UUID):
+            return obj.hex
+        return json.JSONEncoder.default(self, obj)
diff --git a/smart_selects/widgets.py b/smart_selects/widgets.py
index d0c06af..a16788e 100644
--- a/smart_selects/widgets.py
+++ b/smart_selects/widgets.py
@@ -4,6 +4,7 @@
 
 from django.apps import apps
 from django.conf import settings
+
 try:
     from django.core.urlresolvers import reverse
 except ImportError:
@@ -14,6 +15,7 @@
 from django.utils.encoding import force_text
 from django.utils.html import escape
 
+from smart_selects.encoders import UUIDEncoder
 from smart_selects.utils import unicode_sorter, sort_results
 
 get_model = apps.get_model
@@ -253,7 +255,7 @@ def render(self, name, value, attrs=None, choices=(), renderer=None):
 
         attrs["data-chainfield"] = chain_field
         attrs["data-url"] = url
-        attrs["data-value"] = "null" if value is None else json.dumps(value)
+        attrs["data-value"] = "null" if value is None else json.dumps(value, cls=UUIDEncoder)
         attrs["data-auto_choose"] = auto_choose
         attrs["name"] = name
         final_attrs = self.build_attrs(attrs)