This research is an intervention study that compares the impacts of two methods of ethics education, lectures and problem-based learning, on moral sensitivity and reasoning of nursing students of Hamedan University of medical science. In this study, fourth-year nursing students (semester seven and eight) based on drawing, are divided into two classes of lecture and problem-based learning (PBL). Then nursing ethics education programs include definitions of ethics, ethics areas of study, importance of ethics in nursing, nursing ethics principles and their definition (autonomy, confidentiality, accountability, etc.), professional ethics, codes of nursing ethics, approaches to ethical decision making and ethical decision-making process are developed. Contents of both education program are the same, except one of them uses PBL and the other uses lecture learning method. First, goals, intervention methods and appraisal procedure are presented. Before beginning the course, both classes are examined using research tools including ethical sensitivity in decision making and ethical reasoning questionnaire “nursing dilemma test”. The only difference between two classes is in ethical scenario solution, which in lecture class is provided by educator and in PBL class by students. The contents provided for two classes are the same. Sampling method is enumeration. The sample size of students of semester 7 and 8 are 41 and 39 respectively.