Purpose - The purpose of this paper is to focus on the effects of the ethical climate in Chinese certified public accounting (CPA) firms on auditors' perceptions of organizational-professional conflict (OPC) and affective organizational commitment (OC). We also test for differences in the perceived ethical climates of local and international CPA firms. Design/methodology/approach - The study is based on a survey of 167 professional auditors (seniors and managers) employed by local and international CPA firms operating in the People's Republic of China. Findings - Certain dimensions of the perceived ethical climate are significantly related to OPC, and to affective OC. As anticipated, there was also a strong negative relationship between OPC and OC. There was no clear pattern of differences in the perceived ethical climates in local and international CPA firms. Impression management was highly correlated with OPC, OC, and three of four ethical climate dimensions, suggesting that Chinese auditors bias their reports of these variables in a socially desirable fashion. Originality/value - To our knowledge, this is the first study to address the relationship between ethical climate and OPC, and the first to examine OPC and OC among auditors in Mainland China. The findings support our contention that the perceived ethical climate is a key determinant of OPC, suggesting that future research on OPC should place more emphasis on organizational characteristics. In addition, the apparent tendency of auditors to bias their reports of OPC, OC, and ethical climate stresses the importance of controlling for social desirability response bias in surveys of professional accountants.