Abstract: Nowadays, the rate of parasitic contamination can be estimated in at least two ways. One is based on clinical referrals and the other is via measurement of the contamination in domestic raw wastewater. This study aimed to investigate the difference of results between these types. This study was carried out during five months during spring and summer seasons. In total, 90 samples were collected every 5 days from the input raw wastewater and to determine the concentration of ova, samples were analyzed by Mc Master slide according to Bailenger method. The data obtained from the laboratories of the city of Kermanshah in published papers and thesis done as results of clinically parasitic infection was considered. The results indicated that greatest number of parasite eggs in raw wastewater of Kermanshah belongs to Ascaris lumbricoides and Hymenolepis nana eggs. While, the results of parasitic contamination considering clinical referrals were lowest number. Trichuris trichiura reported relatively low rate in both the two types. The statement of parasitic contamination based on clinical referrals and raw sewage was dissimilar and it is more reliable to measure parasitic contamination of sewage than to examine the clinical referrals since the former results sound more real rather latter. The identified parasitic agents in this condition belong to the community as a whole.