Up until the recent past, zoos served limited function, primarily existing for entertainment value. Today’s zoos, however, are serving many roles, chief among them: species conservation of captive animals. The biggest zoo in Brazil, S?o Paulo Zoological Park Foundation, has among its 2000 animals and many species of wild cats. The presence of domestic cats living freely in zoos is common and can be a source of spreading disease. The aim of this study was to verify the variety and prevalence of parasites found in the feces of felids (feral and wild) living in the S?o Paulo Zoo. The results of this parasitological analysis have been obtained from the laboratory of clinical analysis and correspond to the 4-year period beginning January/2009 and ending December/2012. Eight species of parasites were identified in the feces of captive wild cats and three in the feces of feral cats. For those captives, Toxocara cati (7.95%) had the highest prevalence, followed by Toxascaris leonina (7.58%), Isospora sp. (2.03%), Hymenolepis nana (0.92%), Eimeria sp., Giardia sp. and Blastocystis sp. (0.37% each) and Ascaris sp. (0.18%). Among the feral cats, we found Toxocara cati (59.26%), Giardia sp. (22.22%) and Isospora sp. (11.11%). For the captive group, we also distinguished natives from exotic species, finding native species to be more frequently parasitized than the exotic ones. Key to our findings, though, was the fact that a few parasite species were found among all groups of felids, specifically (Toxocara cati, Giardia sp. and Isospora sp). Further research is needed, however, to confirm that transmission of these parasites is occurring between and among these groups.