Auditors’ professional scepticism is a topical concern for the audit profession and public interest. This study examines professional scepticism among fraud auditors in the forensic accounting profession in China (CN) and the United States (US). Data are collected from 373 and 401 CN and US auditors, respectively, in two economies with cultural differences. The multinomial logistic regression results indicate that both CN and US fraud auditors have higher levels of professional scepticism than general auditors do. There are no significant differences in traits between CN and US fraud auditors. High-ranking fraud auditors have higher levels of professional scepticism than junior-ranking fraud auditors for both CN and US auditors. The results of our sensitivity analysis validate the main results and indicate the findings’ robustness. Results support the normative pillar of the institutional theory (Scott 1995) that asserts actors (fraud auditors) of institutions would share common norms and beliefs in a social system because they are rooted in professional affiliations (accounting bodies) (DiMaggio and Powell 1983). Our findings contribute to the literature in the arena of the interests of the public and the economy.