diff --git a/Lib/collections/__init__.py b/Lib/collections/__init__.py
--- a/Lib/collections/__init__.py
+++ b/Lib/collections/__init__.py
@@ -427,6 +427,7 @@
     namespace = dict(__name__='namedtuple_%s' % typename)
     exec(class_definition, namespace)
     result = namespace[typename]
+    result._fields = tuple(map(_sys.intern, result._fields))
     result._source = class_definition
     if verbose:
         print(result._source)