Abstract: According to the unified sampling and diagnostic method which was standardized for survey of human parasite distribution nationwide, data of Ascaris lumbricoides was acquired from some sampling sites in 1989. At 17 sampling sites, the total number of persons under study was 7 980, the positivity was recorded in 2460 cases with a positive rate of 30.8%. The infection rate was 29.8% for males, and 32.3% for females. There was a significant difference between males and females. The survey showed that the increase in age was accompanied by a decrease in infection rate. There was no significant difference between Hui and Han nationalities.