Background: The important shortage of organ donors is still a fundamental public health problem in France. Improving the knowledge and attitudes of health care professionals could help to promote organ donation. The aim of this survey was to evaluate the level of knowledge of medical students and their gaps about organ donation prior to any medical course. Materials and Methods: A survey was conducted among 571 first-year medical students at a medical faculty in Lyon. Their knowledge, attitudes, personal views, and perceptions toward organ donation and transplantation were investigated prior to any medical course. A 31-item anonymous questionnaire including queries about personal views of organ donation, factual knowledge, and awareness of French law was distributed to the students. Results: To "willingness to donate a kidney to a relative," 97.7% of respondents consented, 0.9% objected, and 1.4% did not answer. Their attitudes toward cadaveric organ donation were different: 81.1% agreed, 13.5% refused, and 5.4% did not answer. Regarding their knowledge about which organs could be transplanted, 95% of the respondents were aware of the possibility to transplant a face and 14% thought that xenotransplantation was performed nowadays. Conclusions: First-year medical students have a good knowledge level regarding the organ donation and transplantation system prior to their medical course. Some gaps remain which could be improved. The results of this study supported a greater emphasis on providing information regarding transplantation in medical schools to improve the knowledge of future health care professionals. A follow-up survey of the participants at the end of their medical course will be interesting to assess the progress of their attitudes. © 2009.