This study was carried out to determine the effects of peer education on breast self-examination (BSE) knowledge and health beliefs. 180 female university students were trained in BSE by the nursing students. Students instructed in groups by their peers showed a much higher degree of BSE knowledge. It was also found that perceived confidence of the students educated both individually and in groups increased afterward. Study results further revealed that the methods used for peer instruction do not affect students' sub-dimensions of health beliefs differently after the education.