Nurses are often faced with serious situations that require high levels of legal and ethical knowledge, and should therefore be sensitive to the moral issues in their profession in the decision making process. Some studies have investigated nurses' moral self-concept as an effective factor in moral sensitivity, but there is not sufficient evidence to support this. The purpose of this study was to determine the correlation between moral sensitivity and moral self-concept in nurses employed in the teaching hospitals in Zahedan, Iran. This cross-sectional descriptive study aimed to study the relationship between moral self-concept and moral sensitivity in nurses employed in the teaching hospitals affiliated with Zahedan University of Medical Sciences. Chang's Moral Self-Concept Questionnaire and Lutzen's Moral Sensitivity Questionnaire were used for data collection. Data analysis was performed using SPSS software version 17. A total of 188 nurses participated in this study. The results showed that there was a positive and significant relationship between moral self-concept and moral sensitivity (P < 0.05). Based on our findings, an individual's attention to moral issues can lead to greater sensitivity and result in morally responsible behavior at the time of decision making. Consequently, promotion of moral self-concept through personal effort or education can increase moral sensitivity, which in turn leads to behavioral manifestations of ethical knowledge.