diff --git a/doc/conf.py b/doc/conf.py
index 19c802a..1a8645c 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -47,7 +47,7 @@
 todo_include_todos = True
 
 # atsphinx.mini18n
-mini18n_default_language = "ja"
+mini18n_default_language = "en"
 mini18n_support_languages = ["en", "ja"]
 mini18n_basepath = "/mini18n/"