The current study was conducted in Basrah province during the period from Dec. 2020 to Oct. 2021. The purpose of the study was to determine the seroprevalence of IgG and IgM antibodies of toxoplasmosis in cancer patients in Basrah province, southern Iraq, using the enzyme-linked immunosorbent assay (ELISA). This study was conducted on 173 people, including 123 people with cancer who were taking chemotherapy and 25 healthy people as a first control group and 25 people with cancer who were not taking chemotherapy were considered as a second control group. The results showed that the incidence of chronic) IgG) toxoplasmosis was 31 and acute (IgM) toxoplasmosis was 0.8%.