Abstract: To provide an epidemiologic investigation of the seroprevalence of antibodies to Toxoplasma gondii in sheep population in Chaharmhal and Bakhtiari province (Iran) this study was conducted, the province containing five townships, (Shahrekord, Borujen, Farsan, Ardal and Lordegan). One thousands serum samples (600 female and 400 male) were examined to detect antibodies to T. gondii by Indirect Fluorescent Antibody Test (IFAT). Serological results showed that the seroprevalence of antibodies to T. gondii was 29.1%. The seroprevalence in the townships were 38, 22.5, 32, 35 and 18%, respectively. The results of titration of positive samples showed the following titers:11% with 1/20, 9.3% with 1/40, 15.1% with 1/80, 28.9% with 1/160 and 35.7% with/320 or more. There was no significant difference between the two sexes, while there was a significant difference between the townships located in east and west of the province.