The author studied the beta-glucuronidase activity in the urine of 46 males and 19 females with trematodes such as Clonorchis sinensis, Stellantchasmus falcatus, metagonimus yokogawai, paragonimus westermani, Heterophyes heterophyes. Specific activity of beta-glucuronidase was analyzed statistically by sex, age, intensity of infection and mixed infection. The results obtained in this studies were summarized as follows. In the 41-50 years of age groups of males, beta-glucuronidase activity in the urine was elevated the highest with 1.56U/ml, 1.21U/ml of females and 1.49U/ml of male in the 30-40 years of age groups, but activity of beta-glucuronidase in the urine according to age and sex was not statistical significance. It was gradually increased beta-glucuronidase activity in urine of males and females according to number of mixed infection of trematodes species(p<0.01). beta-glucuronidase activity in urine of males and females according to intensity of trematodes infection appeared 0.92U/ml in the simple infection, 1.14U/ml in the medium infection and 1.54U/ml in the heavy infection, respectively(p<0.01). On the basis of results, it was suggested that beta-glucuronidase activity in the human urine was significantly increased in the intensity of infection and mixed infection groups than that of normal groups.