Abstract: Toxoplasmosis is one of the most prevalent parasitic infections of man and livestock, and its transmission has usually been attributed to ingestion of undercooked or raw meat from infected livestock, with the infection rate in those animals being an important risk predictor of human disease, high in Iran and ardabil State. Looking for this public health problem, we tested serum samples from cattle, goat, sheep and chicken from the State of ardabil, Iran, for IgG antibodies toToxoplasma gondii by enzyme-linked immunosorbent assay (ELISA). Antibodies toToxoplasma gondii were found in 30.00% (60/200) of sheep, 15.00% (30/200) of goat and 9.00% (18/200) of cattle, without positive sample in chicken. Despite differences in feeding habits of each species, the rate of infection of tested animals could be better attributed to livestock management methods, which improvement could reduce infection.