To assess a polential relationship of Korean ginseng to allergic reactions, the effect of Korean ginseng on the total IgE in serum as an allergologic parameter was investigated in humans. Serum total IgE levels were measured in 8 subjects who have been taking ginseng for more than 5 years, 4 subjects of weak constitution, 10 newly hired workers in the ginseng processing industry and 7 normal subjects unexposed to Korean ginseng as control group. Blood samples were taken before and after the exposure to Korean ginseng. Total IgE levels after the exposure to Korean ginseng were not significantly different from those before the exposure within each group. And also, the IgE levels of control subjects were not significantly different compared with those of other groups. These results suggest that the exposure to Korean ginseng dose not affect significantly the IgE immune response of the subjects.