Although surgical site infections have decreased with the use of prophylactic antibiotics, inappropriate surgical antibiotic prophylaxis is still a world-wide problem. In this retrospective study, perioperative antibiotic prophylaxis was evaluated in a university hospital. All surgical procedures (total 2038) performed in the year 2002 were included. The study setting was the Anesthesiology and Reanimation unit in Pamukkale University Medicine Faculty Hospital. A total of 1902 patients received antibiotic prophylaxis. Ninety-two percent of all procedures were elective, 8% emergencies. Approximately 85.7% were clean surgery, 8.5% clean-contaminated, 5.3% contaminated, and 0.5% dirty. Approximately 93.3% of patients received antibiotic prophylaxis. Although timing of prophylaxis was appropriate in all procedures, duration was optimal in only 29.0% of all cases. Sulbactam/ampicillin (33.2%), cefepime (23.4%), ceftriaxone (15.1%), ciprofloxacin (12.6%) and cefazolin (11%) were the most commonly used antibiotics. Instead of an estimated optimal cost of perioperative antibiotic prophylaxis ranging between US$2.6 and 7.8 according to guidelines, the average cost was US$62 per patient. We believe that compliance regarding the optimal choice, frequency and duration of perioperative antibiotic prophylaxis is inadequate, thereby making additional efforts necessary.