Background Attention to ethical philosophy and in particular ethical theories is necessary for audits. The purpose of this study is to identify and examine the importance of ethical theories in auditing from the perspective of experts and professional activists. Method This research is a combination of qualitative and quantitative methods. Qualitative part is conducted by Delphi and content analysis. Population of the study includes all related articles with ethical philosophy. Based on the opinion of three experts, 25 related articles were identified and, using content analysis identified eight ethical theories that are prominent in the audit profession. Then, with the Delphi technique and using the opinion of 13 experts, the importance of these theories was identified. Also, in the quantitative section, there is a research community of active auditors in the country that prioritizes theories of ethics by obtaining 164 opinions through simple random sampling and questionnaire tools and data were analyzed with LISREL software. Results The findings of the study showed that according to the expertschr('39') viewpoints, from all eight theories examined (conservatism, utilitarianism, autism, altruism, justice, libertarianism, benevolence, and virtue), all except Selfishness and liberalism matter more than the average. The survey of professional activistschr('39') opinions also showed that all the 6 theories examined apply to the Iranian audit environment and have a higher than average importance. Also, benevolence has the highest factor loadings, followed by virtue-oriented theories, conscientiousness, justice, altruism, and utilitarianism, respectively. Conclusion To increase the level of professional ethics, it is necessary to pay attention to ethical theories by the identified priorities.