Cats are the only species that pass the environmentally resistant oocyst in feces and sporulated oocysts are infectious to humans and other animals. This is the reason why cats were always accused to be the main source of Toxoplasma gondii infection and very often they have no clinical signs. A seroprevalence study of Toxoplasma gondii antibodies was performed in household and stray cats (92 cat sera were examined: 60 household cats and 32 stray cats). The survey for the determination of antibodies for Toxoplasma gondii was done by the usage of complement fixation test technique. The overall seroprevalence was 17.3%. The infection rate in stray cats was higher (35.8%) than in household cats (15.2%). Last serum positive dilutions varied from 1:40 to 1: 640, for the both groups of cats. All of the cats were adult ones, so the correlation between the age and the rate of infection was not observed and most of them were females (90%), so the difference between sexes was not significant. None of the cats had any clinical signs. Gained seroprevalence results among the cats are significant, especially among stray cats, since they usually live close to humans or other animals, and can be the source of toxoplasmosis.