diff --git a/data/class/SC_CheckError.php b/data/class/SC_CheckError.php
index 29ec38dcfe..797e32fbed 100644
--- a/data/class/SC_CheckError.php
+++ b/data/class/SC_CheckError.php
@@ -74,7 +74,7 @@ public function HTML_TAG_CHECK($value)
 
         // HTMLに含まれているタグを抽出する
         $match = array();
-        preg_match_all('/<\/?([a-z]+)/i', $this->arrParam[$keyname], $match);
+        preg_match_all('/<\/?([a-z\d]+)/i', $this->arrParam[$keyname], $match);
         $arrTagIncludedHtml = $match[1];
         // 抽出結果を小文字に変換
         foreach ($arrTagIncludedHtml as $key => $matchedTag) {
diff --git a/html/install/sql/insert_data.sql b/html/install/sql/insert_data.sql
index bcf5aa6592..e6e4f8acde 100644
--- a/html/install/sql/insert_data.sql
+++ b/html/install/sql/insert_data.sql
@@ -737,7 +737,6 @@ INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (5, 'blink', 5);
 INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (6, 'br', 6);
 INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (7, 'center', 7);
 INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (8, 'font', 8);
-INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (9, 'h', 9);
 INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (10, 'hr', 10);
 INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (11, 'img', 11);
 INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (12, 'li', 12);
@@ -747,6 +746,12 @@ INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (15, 'div', 15);
 INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (16, 'i', 16);
 INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (17, 'u', 17);
 INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (18, 's', 18);
+INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (19, 'h1', 19);
+INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (20, 'h2', 20);
+INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (21, 'h3', 21);
+INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (22, 'h4', 22);
+INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (23, 'h5', 23);
+INSERT INTO mtb_allowed_tag (id, name, rank) VALUES (24, 'h6', 24);
 
 INSERT INTO mtb_authority (id, name, rank) VALUES (0, 'システム管理者', 0);
 INSERT INTO mtb_authority (id, name, rank) VALUES (1, '店舗オーナー', 1);