summary. We determined the seroprevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) among health care workers (HCWs) at Gülhane Military Medical Academy, Haydarpasa Training Hospital in Istanbul, Turkey. Between April 1998 and September 2000, 702 HCWs were included in the study. The blood samples were tested for hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs) and HCV antibody (anti-HCV) using third-generation tests, with confirmation by reverse transcriptase-polymerase chain reaction. Seroprevalence rates were compared with those detected in 5670 blood donors during the same period. HBsAg, anti-HBs and anti-HCV were detected in 21 (3.0%), in 480 (68.4%) and in 2 (0.3%) of 702 HCWs respectively. HBsAg and anti-HCV rates were 2.1 and 0.4% in blood donors, respectively. These data show that the prevalence rates of HBV and HCV were similar with prevalence rates detected in randomized blood donors showing that universal infection-control precautions and encouraging HBV vaccination reduces HCW infection with hepatotropic viruses.