The study for positivities of hepatitis B surface antigen (HBsAg) by RPHA and hepatitis B surface antibody (anti-HBs) by PHA and transaminases (SGOT and SGPT) by kinetic method were performed in the months, from March to October 1992 among the steel related industrial workers who were residents of Pohang city. The results were as follows; The positive rate of HBsAg in all subjects was 7.5%, (1089/14472) and that of anti-HBs was 30.7%, (4439/14472). The positivities of HBsAg and anti-HBs in male subjects (7.6%, 30.8%) Were significantly higher than in females (3.7%, 26.3%) (p<0.01. p<0.05 respectively). The positive rates of HBsAg and anti-HBs were increased with age. In males those were significantly higher in their thirties (8.0%, 31.7%) than in their twenties (6.8%, 28.5%) (p<0.05, p<0.001 respectively). The anti-HBs positive rate of females in their forties (54.2%) was significantly higher than that of females in their thirties (29.2%) (p<0.05). The positivities of HBsAg and anti-HBs arrording to educational background or work type in male had no significant differences in either groups (Table 4, 5, 8, 9). There were no significant differences in the positive rates of HBsAg according to the workfield in either groups. But the positive rate of anti-HBs in blue collar workers (31.2%) was significantly higher than that of white co]lar workers (27.0% ) (p < 0.01). There were significant differences between the positive rates of HBsAg in males.according to the liver function test (LFT: SGOl and SGPT) which were 6.0% with normal LFT and 21.2% with abnormal LFT (p<0.01). In conclusion, the positive rate of HBsAg was largely influenced by sex, age and LFT but not influenced by educational background, work field or work type. The positive rate cf anti-HBs was largely inflnenced by sex, age and work field but practica@1ly unaffected by educational background or work type.