The objectives of this study were to evaluate the occupational risk of medical students, their knowledge and practice of universal biosafety measures and hepatitis B immunization coverage. A specific questionnaire was applied to 136 medical students of the Universidade Federal de Minas Gerais: 87 (64%) students were involved in surgical procedures, 68 (50%) had been exposed to blood, 90 (66.2%) knew the universal biosafety measures and 33 (24.3%) knew the procedure in case of blood exposure. Thus, this population has a high risk of blood exposure and although there is a low formal knowledge about universal biosafety measures, most of these were generally used. New strategies, such as formal teaching of universal biosafety measures, in loco supervision, and biosafety teams, are necessary to change this situation.