Accountants' ethical decision-making as an effective factor in providing honest financial reports can be influenced by factors such as personal characteristics and mental health. Psychological well-being as one of the fields of behavioral finance has an effect on accountants' ethical decision-making. In the meantime, people's willingness to take risks, under the influence of people's mental and psychological characteristics, can affect the level of ethical decisions taken by them. The purpose of this research is to investigate the effect of psychological well-being on the ethical decision-making of accountants, taking into account the mediating role of individual risk-taking tendency. The research data was obtained using standard questionnaires by a sample using Cochran's formula, 165 people randomly selected from among 290 accountants of tile companies in Yazd province in 1401. Data analysis has been done using structural equation method and PLS software. Based on the findings of the research, psychological well-being has a positive and significant effect on the ethical decision-making of accountants through the willingness to take individual risks. On the other hand, psychological well-being has a direct effect on the tendency to take risks, and the tendency to take risks has an inverse effect on ethical decision-making. The findings of this study can be useful in developing recruitment strategies and training programs for accountants in firms.