diff --git a/src/components/seo.js b/src/components/seo.js
index 2bca1e0..d844012 100644
--- a/src/components/seo.js
+++ b/src/components/seo.js
@@ -82,7 +82,7 @@ function SEO({ description, lang, meta, keywords, title }) {
 }
 
 SEO.defaultProps = {
-  lang: `en`,
+  lang: `ja-JP`,
   meta: [],
   keywords: [],
 };