Abstract: According to the unified scheme for nationwide survey of human parasites, a pilot investigation was carried out in 102 spots randomly selected from 25 counties/cities in Guizhou Province in 1987-1991. A total of 52 938 people were subjected to stool examination. The overall intestinal parasitic infection rate was 81.0%. The detected 21 species and their infection rates were exhibited, i.e. Ascaris lumbricoides 71.1%, Trichuris trichiura 29.1%, hookworm 22.9%, Enterobius vermicularis 4.7% (under 12 years old), Trichostrongylus sp. 0.03%, Trichostrongylus orientalis 0.2%, Strongyloides stercoralis 0.3%, Rhabditis sp. 0.07% , Oesophagostimum s p. 0.07%, Fasciolopsis buski 0.01%, Taenia sp. 0.03%, Hymenolepis diminuta 0.01%, Entamoeba histolytica 2.3%, Entamoeba coli 5.5%, Entamoeba hartmanni 0.5%, Endolimax nana 1.7%, Iodamoeba buetschlii 0.8%, Giardia lamblia 1.5% , Trichomonas hominis 0.004%, Blastocystis hominis 0.08% and Isospora sp.0.002%. A significant correlation between parasitic infections and socioeconomic factors was indicated. Differences in geographical distribution of parasites were also noted. Polyparasitism was very common, while intensity of infection was rather low. The infection rate was higher in minorities than in Hans, and higher in students and farmers than in others. The age group of 10-19 years old was the most vulnerable one. Apparent tendency of family clustering was indicated in parasitic infections of A. lumbricoides, T.trichiura, hookworm, E. coli and G. lamblia. Summing up the preceding species and the parasites recorded in literature, the total number of human parasite species was thus noted as 27 in the province.