diff --git a/Lib/test/test_sgmllib.py b/Lib/test/test_sgmllib.py
index b6986360ac1..f0f8ad6d322 100644
--- a/Lib/test/test_sgmllib.py
+++ b/Lib/test/test_sgmllib.py
@@ -366,7 +366,7 @@ def test_read_chunks(self):
         # Just verify this code doesn't cause a hang.
         CHUNK = 1024  # increasing this to 8212 makes the problem go away
 
-        f = open(test_support.findfile('sgml_input.html'))
+        f = open(test_support.findfile('sgml_input.html'), encoding="latin-1")
         fp = sgmllib.SGMLParser()
         while 1:
             data = f.read(CHUNK)