diff --git a/.vuepress/config.js b/.vuepress/config.js
index 16c151f..b0e3e52 100644
--- a/.vuepress/config.js
+++ b/.vuepress/config.js
@@ -65,7 +65,7 @@ module.exports = {
     '@vuepress/back-to-top': {},
     '@vuepress/last-updated': {
       transformer: (timestamp, lang) => {
-        return dateFns.format(timestamp, 'yyyy-MM-dd HH:mm:ss')
+        return dateFns.format(timestamp, 'YYYY-MM-DD HH:mm:ss')
       }
     },
     'vuepress-plugin-code-copy': {