diff --git a/IPython/frontend/html/notebook/notebookmanager.py b/IPython/frontend/html/notebook/notebookmanager.py
index 15d8bb471da..78ca7615947 100644
--- a/IPython/frontend/html/notebook/notebookmanager.py
+++ b/IPython/frontend/html/notebook/notebookmanager.py
@@ -213,7 +213,7 @@ def save_notebook_object(self, notebook_id, nb):
         if self.save_script:
             pypath = os.path.splitext(path)[0] + '.py'
             try:
-                with io.open(pypath,'w') as f:
+                with io.open(pypath,'w', encoding='utf-8') as f:
                     current.write(nb, f, u'py')
             except Exception as e:
                 raise web.HTTPError(400, u'Unexpected error while saving notebook as script: %s' % e)