diff --git a/htdocs/core/lib/ajax.lib.php b/htdocs/core/lib/ajax.lib.php
index 041235682d2..cc5ca841c52 100644
--- a/htdocs/core/lib/ajax.lib.php
+++ b/htdocs/core/lib/ajax.lib.php
@@ -305,6 +305,7 @@ function ajax_combobox($htmlname, $event=array(), $minLengthToAutocomplete=0)
 	global $conf;
 
 	if (! empty($conf->browser->phone)) return '';	// combobox disabled for smartphones (does not works)
+	if (! empty($conf->global->MAIN_DISABLE_AJAX_COMBOX)) return '';
 
 	/* Some properties for combobox:
 	minLengthToAutocomplete: 2,