For hospital personnel, transmission of virus is a common and serious occupational hazard. Other than suffering from physical discomfort, these infected hospital staffs may also transmit the disease to patients through their blood, mucous or secretion contamination. The purpose of this study is intended to understand the condition of hepatitis B virus infection between anesthetists and hospital administration staffs. Forty-six anesthetists (study group) and 90 hospital administration staffs (control group) were volunteers of the study. Blood samples for serologic and biochemical test of hepatitis B virus infection in each participant were proceeded from October to December 1990. To investigate personal recognition about hepatitis B infection, each was requested to fill up a questionnaire after blood sampling. We also retrieved the chart of all participators for their annual hepatitis B serologic result in order to find out the incidence of seroconversion. Among the 136 participators, 20 (14.7%) were HbsAg carriers. Only 28 (20.6%) of all the participators were free from infection and seronegative. However, it was found that there was no significant difference (P greater than 0.05) between the two groups, no matter in HbsAg positive or seronegative incidence. There was 10 (1.27%) incidence of seroconversion during 790 times of person-year observation. Though not significant (P less than 0.05), there was a double fold (2.2 times) seroconversion rate in the study group than that of the control group. Twenty (19.9%) seropositive participators knew that they are hepatitis B carrier or had been infected. Generally, anesthetists seemed better than hospital administration staffs in realizing that they were infected or carrier from the data of serological test.(ABSTRACT TRUNCATED AT 250 WORDS)