Nurses are often faced with complex situations that made them to make ethical decisions; and to make such decisions, they need to possess the power of moral reasoning. Studies in Iran show that the majority of nursing students lack proper ethical development. Socratic teaching is a student-centered method which is strongly opposed to the lecturing method.

This study was conducted to evaluate the impacts of Socratic questioning on the moral reasoning of the nursing students.

In a quasi-experimental study, Crisham’s Nursing Dilemma Test was used to evaluate the results of three groups before, immediately after, and 2 months after intervention. The data were analyzed using the SPSS statistical software (v 15).

Through random allocation, 103 nursing students were divided into three groups. In experiment group 1 (37 students), intervention consisted of Socratic questioning-based sessions on ethics and how to deal with moral dilemmas; experiment group 2 (33 students) attended a 4-h workshop; and the control group (33 students) was not subject to any interventions.

This research was approved by the Ethics Committee of the University. All the participants signed written informed consents.

There were significant differences between experiment group 1 and experiment group 2’s pre-test and post-test scores on moral reasoning (p ≤ 0.001, p ≤ 0.001), nursing principled thinking (p ≤ 0.001, p ≤ 0.001), and practical considerations (p ≤ 0.001, p ≤ 0.031).

Both the teaching approaches improved the subjects’ moral reasoning; however, Socratic questioning proved more effective than lecturing. Compared to other similar studies in Iran and other countries, the students had inadequate moral reasoning competence.

This study confirms the need for the development of an efficient course on ethics in the nursing curriculum. Also, it appears that Socratic questioning is an effective method to teach nursing ethics and develop nursing students’ competence of moral reasoning.