diff --git a/nltk/corpus/reader/childes.py b/nltk/corpus/reader/childes.py
index e726a709d1..07cbf8349f 100644
--- a/nltk/corpus/reader/childes.py
+++ b/nltk/corpus/reader/childes.py
@@ -20,7 +20,7 @@
 from nltk.util import LazyConcatenation, LazyMap, flatten
 
 # to resolve the namespace issue
-NS = "https://www.talkbank.org/ns/talkbank"
+NS = "http://www.talkbank.org/ns/talkbank"
 
 
 class CHILDESCorpusReader(XMLCorpusReader):