In the 2,218 healthy cases-male 1,574 female 644-who were conducted serum examination from May 1st 1983 to November 1st 1983 by the medical selection of Dae Han Kyouk life insurance Co., the results which investigated the HBsAg by using the Reverse Passive Hemagglutination(RPHA) method are as follows; 1. The number of 167 from 2,218 cases proved to be positive, showing 7.52%, the number of 143 from 1,574 male positive, showing 9.08%, and the number 24 from 644 female positive, showing 3.73%. The positive rate of the male was indicated by 5.36% higher than that of the female as the former marked 2.4 times higher distribution than the latter. 2) The positive rate by the type of occupations appears as follows; The highest positive rate group is that of discharger from military service in 1983, the number of 70 from 736 persons marking 9.51% and the next is the merchant 8.79%(8/91), employee of a company markes 8.53%(44/516), high school boy 7.69%(19/247), house wife 5.71%(10/210), carrier woman 3.45%(10/290) and the group of the high school girl records the minimum rate of all, 3.13%(4/128). 3. The positive rate by the age group appears as follows; The highest rate group is that of 31 to 35 years, marking 9.80% positive rate, and the next is $26{sim}30$(9.3%), $21{sim}25$(8.01%), $41{sim}45$(6.96%), $36{sim}40$(6.9%), those below 20(5.99%), 46 to 50 years shows the minimum rate of all(2.94%) Among the male case, 26 to 30 years shows the highest positive rate by 10.59% and female, 31 to 35 years shows the highest rate by 7.89%. 4. The positive rate by the blood type represents as follows; Blood type A shows 7.30%, type B 7.17%, type O 6.11% and type AB indicates 5.88% in order.