diff --git a/po/ja.po b/po/ja.po
index f2d85012e0..48f2803b7a 100644
--- a/po/ja.po
+++ b/po/ja.po
@@ -1398,7 +1398,7 @@ msgstr "金"
 
 #: js/messages.php:192
 msgid "Saturday"
-msgstr ""
+msgstr "土"
 
 #. l10n: Short week day name
 #: js/messages.php:196 libraries/common.lib.php:1593