You probably use QLinkButton which is rendered as a tag <a href=“#”>
Probably you need to add QTeminateAction to the control something like this:
$this->btnSubmit->AddAction(new QClickEvent(), new QAjaxAction('btnSubmit_Click'));
$this->btnSubmit->AddAction(new QClickEvent(), new QTerminateAction());
or edit the control to make html it renders doesn't containt the #.
Hope it helps if not please post some code.