The aim of this study was to detect the seroprevalences of Toxoplasmosis, brucellosis and listeriosis in horses from the Hakkari city, eastern region of Turkey. For this purpose, serum samples from 74 local horses were obtained and tested using IHA and Sabin-Feldman Dye tests (SFDT) for toxoplasmosis, Serum Tube Agglutination test (SAT) for brucellosis and Osebold Agglutination Test (OAT) for listeriosis. The toxoplasmosis seroprevalences detected with MAT and with SFDT were 13.5% and 28.3% respectively, the SFDT presenting a higher sensitivity. The seroprevalence of brucellosis was low in horses (9.5%) while a high seroprevalence of listeriosis (48.6%) was evidenced. No significant association between age or sex and toxoplasmosis or listeriosis infections was observed. By contrast, brucellosis seroprevalence was significantly higher in females than in males. These results suggest that horses from the Hakkari region can be considered as potential reservoirs for these infectious agents for other species and may contribute to the disease spreading and to direct (brucellosis, listeriosis) and indirect (toxoplasmosis) contamination of humans.