This study investigates whether the appointment of a female to the audit committee of a foreign issuer in the US is positively associated with subsequent market price reaction. We hypothesize that female members on the audit committee can strengthen corporate governance by their conservative and ethical qualities. Accordingly, such appointments deliver a positive message to capital market participants. In order to observe the impact of audit committee gender diversity on foreign firms, we include all audit committee appointments for US-traded foreign firms from 2002 to 2009. We find that the appointment of female audit committee members has significant positive cumulative abnormal returns compared to the appointment of male audit committee members.