diff --git a/htdocs/api/class/api.class.php b/htdocs/api/class/api.class.php
index 36eb7c1d7d2..d76759532dc 100644
--- a/htdocs/api/class/api.class.php
+++ b/htdocs/api/class/api.class.php
@@ -48,7 +48,7 @@ class DolibarrApi
      */
     function __construct($db, $cachedir='', $refreshCache=false)
     {
-        global $conf;
+        global $conf, $dolibarr_main_url_root;
 
         if (empty($cachedir)) $cachedir = $conf->api->dir_temp;
         Defaults::$cacheDirectory = $cachedir;
@@ -57,6 +57,8 @@ class DolibarrApi
         $production_mode = ( empty($conf->global->API_PRODUCTION_MODE) ? false : true );
         $this->r = new Restler($production_mode, $refreshCache);
 	$this->r->setBaseUrls(DOL_MAIN_URL_ROOT, $urlwithroot);
+	$urlwithouturlroot=preg_replace('/'.preg_quote(DOL_URL_ROOT,'/').'$/i','',trim($dolibarr_main_url_root));
+	$urlwithroot=$urlwithouturlroot.DOL_URL_ROOT; // This is to use external domain name found into config file
         $this->r->setAPIVersion(1);
     }