Background: Providing health services is described as an important moral measure, since its major aim is to ensure the welfare of the people who need treatment and care. Moral sensitivity is the ability to identify the existing moral problem and understand the moral consequences of the decisions made on the patient’s part. Physicians are always exposed to moral distress due to various circumstances. Objectives: In this survey, we evaluated moral sensitivity and moral distress among physicians and the relationship of these ethical factors on them. Hence, we assessed y relationship between moral sensitivity and moral distress in physicians will facilitate their sound management so as to provide high-quality and safe health services. Moreover it will confirm proposed theories regarding this subject. Materials and Methods: This cross-sectional descriptive-analytic study aimed at investigating the relationship between moral sensitivity and moral distress among 321 specialist physicians working in hospitals affiliated to Tehran Medical Universities in Tehran. The samples were selected through two-stage random cluster sampling method. A three-partite questionnaire comprising of demographic characteristics, moral distress, and moral sensitivity was used for collecting data which then were analyzed using SPSS-20. Results: There was a negative significant relationship between moral sensitivity and moral distress frequency; there was a positive significant relationship between moral sensitivity and moral distress intensity. Participating in medical ethics courses increased moral sensitivity and decreased the frequency of moral distress. Conclusions: Participating in medical ethics courses increased moral sensitivity and decreased the frequency of moral distress.