Over one-third of the world’s population are seropositive for Toxoplasma gondii. One of the important traits of T. gondii is its ability to alter and manipulating the behavior and personality of its intermediate host. The current study was aimed to determine the prevalence of acute and chronic toxoplasmosis in those persons suffer from schizophrenia using serological and molecular techniques. In this cross-sectional study, blood samples were taken from 118 Schizophrenia patients hospitalized in Sistan and Baluchestan province, southeast of Iran. IgM and IgG anti-Toxoplasma antibodies were measured using enzyme-linked immunosorbent assay (ELISA). Furthermore, the presence of parasite was evaluated using nested-PCR B1 gene. Among 118 schizophrenic patients, 48 (40.67%), 4 (3.37%) and 14 (11.86%) were tested seropositive only for IgG, only for IgM and for both of IgG/IgM. So that, total prevalence was 66/118 (55.91%). All samples were also examined using nested-PCR and T. gondii DNA was found in 41 (34.74%) samples. Our study showed high seroprevalence of toxoplasmosis in southeast of Iran.