Based on the research sample of Shanghai and Shenzhen A-share listed family enterprises from 2010 to 2020, this paper empirically tests the relationship between internationalization of family enterprises and audit fees. The results show that the internationalization of family firms increases the audit fees. Inter-generational inheritance and family board seats play positive and negative regulating roles between the two respectively. The mechanism test shows that the international operation of family enterprises increases the operational risks of the enterprises, improves the risk assessment of auditors, and leads to the increase of audit fees. Further research shows that the positive impact between internationalization of family firms and audit fees is more prominent in companies with no overseas executives and companies without state-owned ownership. The conclusion provides theoretical basis and empirical evidence for strengthening the supervision of internationalization of family firms from the perspective of auditors.