Our aim was to investigate the effect of a selective smoking cessation counseling class on the skills and knowledge of medical students. Sixty medical students from Ondokuz Mayis University attended a selective smoking cessation counseling and prevention class (total 96 hours) at 2011-2012 academic year. After attending an initial 8 weeks of lectures, problem-based sessions, case presentations, patient videos and workshops, the students then assisted with the counseling of real smokers in the remaining 4 weeks, under supervision. Students’ knowledge of tobacco dependence, treatment and counseling strategies was scored before (pretest) and after (post-test) the course using a 50-item questionnaire. The students’ skills were evaluated in an Objective Structured Clinical Exam (OSCE). A significant difference was determined between the pretest (12.7±7.6) and post-test (35.8±7.8) results (p<0.001). The mean OSCE score was 89.2±2.7. The smoking cessation counseling and prevention selective class is highly effective in improving students’ cessation counseling skills.