diff --git a/pkg/services/sqlstore/migrations/alert_mig.go b/pkg/services/sqlstore/migrations/alert_mig.go
index 6efdec6b8a7..57e4350a6da 100644
--- a/pkg/services/sqlstore/migrations/alert_mig.go
+++ b/pkg/services/sqlstore/migrations/alert_mig.go
@@ -171,4 +171,8 @@ func addAlertMigrations(mg *Migrator) {
 	mg.AddMigration("Add column secure_settings in alert_notification", NewAddColumnMigration(alert_notification, &Column{
 		Name: "secure_settings", Type: DB_Text, Nullable: true,
 	}))
+
+	// change column type of alert.settings
+	mg.AddMigration("alter alert.settings to mediumtext", NewRawSqlMigration("").
+		Mysql("ALTER TABLE alert MODIFY settings MEDIUMTEXT;"))
 }