diff --git a/Config/Migration/1769652195_add_index.php b/Config/Migration/1769652195_add_index.php
new file mode 100644
index 0000000..9d89bd2
--- /dev/null
+++ b/Config/Migration/1769652195_add_index.php
@@ -0,0 +1,57 @@
+<?php
+/**
+ * インデックス追加のみ。
+ *
+ * @package Researchmap\RmNetCommons\Config\Migration
+ */
+class AddIndex extends CakeMigration {
+
+/**
+ * Migration description
+ *
+ * @var string
+ */
+	public $description = 'add_index';
+
+/**
+ * Actions to be performed
+ *
+ * @var array $migration
+ */
+	public $migration = array(
+		'up' => array(
+			'create_field' => array(
+				'content_comments' => array(
+					'indexes' => array(
+						'idx1_p_content_comments' => array('column' => array('block_key', 'plugin_key','content_key','status'), 'unique' => 0),
+					),
+				),
+			),
+		),
+		'down' => array(
+			'drop_field' => array(
+				'content_comments' => array('indexes' => array('idx1_p_content_comments')),
+			),
+		),
+	);
+
+/**
+ * Before migration callback
+ *
+ * @param string $direction Direction of migration process (up or down)
+ * @return bool Should process continue
+ */
+	public function before($direction) {
+		return true;
+	}
+
+/**
+ * After migration callback
+ *
+ * @param string $direction Direction of migration process (up or down)
+ * @return bool Should process continue
+ */
+	public function after($direction) {
+		return true;
+	}
+}
diff --git a/Config/Schema/schema.php b/Config/Schema/schema.php
index 9f34aa1..b941ed3 100644
--- a/Config/Schema/schema.php
+++ b/Config/Schema/schema.php
@@ -62,7 +62,8 @@ public function after($event = array()) {
 		'modified' => array('type' => 'datetime', 'null' => true, 'default' => null, 'comment' => '更新日時'),
 		'indexes' => array(
 			'PRIMARY' => array('column' => 'id', 'unique' => 1),
-			'block_key' => array('column' => array('block_key', 'plugin_key', 'content_key', 'created'), 'unique' => 0, 'length' => array('block_key' => '191', 'plugin_key' => '191', 'content_key' => '191'))
+			'block_key' => array('column' => array('block_key', 'plugin_key', 'content_key', 'created'), 'unique' => 0, 'length' => array('block_key' => '191', 'plugin_key' => '191', 'content_key' => '191')),
+			'idx1_p_content_comments' => array('column' => array('block_key', 'plugin_key', 'content_key', 'status'), 'unique' => 0)
 		),
 		'tableParameters' => array('charset' => 'utf8', 'collate' => 'utf8_general_ci', 'engine' => 'InnoDB')
 	);