Objectives: To evaluate the seroprevalence of Toxoplasma gondii among Saudi pregnant women in Najran City, as well as to measure the performance of the diagnostic tests used. Methods: A total of 96 women attending prenatal special clinics (Oteafyn special clinic) in Najran Province, Saudi Arabia, over a one year period, from September 2012 to September 2013 were screened for the presence of Toxoplasma antibody in their blood serum using an indirect hemagglutination assay (IHA). Specific immunoglobulin (Ig) G and IgM antibodies were evaluated using an enzyme-linked immunosorbent assay (ELISA). Results: Out of the 96 samples of sera tested using IHA, 20 (20.8%) were found to be positive with a titer ranging from 1:80 to 1:320, while 29 (29.2%) and 3 (3.1%) revealed Toxoplasma IgG and Toxoplasma IgM. A positive relationship was found between the seroprevalence of toxoplasmosis and age of tested women, especially in the age group of 21-30 years old (54.7%) by using ELISA-IgG, and 31-40 years old (4.5%) by using ELISA-IgM. Conclusion: The seroprevalence of Toxoplasmosis among pregnant women was found to be comparatively high, compared with previous reports from Saudi Arabia. Serologic checkup before and during pregnancy for seronegative women is recommended.