Medical wastes are of public health concern in both developed and developing countries being costly in disposal and carry risks of infection or physical injury and of exposure to potentially harmful pharmaceuticals. This study aimed to determine the knowledge and attitudes of intern doctors and emergency nurses in a university hospital and conducted in Gazi University Hospital in April 2006. One hundred and thirty one intern doctors and 27 emergency nurses are targeted to be reached for March April 2006 period. A questionnaire form was filled out for each participant. Nurses have undergone training programs on medical wastes and waste segregation (50.0%) significantly more than the intern doctors (19.3%). The knowledge of the medical wastes that must be disposed in "red coloured plastic sacks" were known by almost all (98.6% of intern doctors, 100.0% of emergency nurses) participants (p > 0.05). Wastes which must be disposed in "blue coloured plastic sacks" and "black coloured plastic sacks" were known better by nurses (85.0 and 85.0%) than intern doctors (60.5 and 58.2%) (p < 0.05). Intern doctors and emergency nurses are found as a group of high risk and the appropriate training programs in terms of timing and content will be effective.