Abstract: In compliance with the regulation and methodology stipulated in the Nationwide Survey of Human Parasite Distribution Program,an investigation on human parasite distribution was conducted inTianjin municipality during 1987-1990. As a consequence, 13 species of parasites comprising 6 species of protozoa and 7 species of helminths were disclosed, showing an integral infection rate of 38.6%. The following species were present in the parasite spectrum: Ascaris lumbricoides 28.3%, Trichuris trichiura 6.9%, Enterobius vermicularis 15.3% , hookworm 0.4%, Clonorchis sinensis 0.2%, Entamoeba histolytica 1.7%, Entamoeba coli 2.3%, Entamoeba hartmanni 0.2%, Endolimax nana 0.9%, Iodamoeba buetschlii 0.3% , and Giardia lamblia 1.7%. The infection rate of A. lumbricoides was found to be higher in females than that in males, but sex based differences were not demonstrated for other species except for G. lamblia (higher rate in males).