Abstract: Background: Education of carcinogens and occupational and environmental cancers to medical sciences students are very important because in the future they can prevent the cancers prevalence in the society. Objective of this study was finding the best way for introduction of occupational and environmental carcinogens to students. Methods: This study was a study which was done by using the occupational health curriculum, the lessons of occupational carcinogen and cancers was taught with attention to educational methods and assessment. Some methods selected for teaching; group (1): evidence based medical education, group (2): group discussion and group (3): teaching to others. Results of exams were compared between three groups of participants, then results of tests and exams were analyzed by SPSS 16, with P<0.05. Results: The total grade of occupational and environmental carcinogens and cancer prevention in group (1) was 17.51±1.09, in group (2) was 16.60±1.01 and in group (3) was 15.54±0.73 had significant differences (P<0.001). The best grade was in group (1) for ultra violet, skin cancer and prevention methods and it had significant difference with P<0.001. Conclusion: According to the total results, evidence based education was the best method for introduction of occupational and environmental carcinogens and cancer prevention.