diff --git a/wchat/common/HttpClient.php b/wchat/common/HttpClient.php
index b6cfa6f..c0b1290 100644
--- a/wchat/common/HttpClient.php
+++ b/wchat/common/HttpClient.php
@@ -171,7 +171,7 @@ class HttpClient
 	public function setHost(string $host)
 	{
 		$this->host = $this->replaceHost($host);
-		$match_quest = '/^[a-zA-Z\-](\.[a-zA-Z\-])*/';
+		$match_quest = '/^[a-zA-Z\-]+(\.[a-zA-Z\-])+/';
 		if (preg_match($match_quest, $this->host)) {
 			$this->addHeader('Host', $this->host);
 		}