A sero-prevalence survey of Toxoplasmosis in domestic animals (sheep, goats and camels) was conducted in the Najran region of Saudi Arabia from August to November 2014 to determine the status of the disease, as well as to evaluate the diagnostic performance of the serological tests used. A total of 263 sera were tested, 85 sheep; 88 goats and 90 camels, for the presence of Toxoplasma gondii antibodies using Indirect Hemagglutination test (IHAT) and enzyme-linked immunosorbent assay (ELISA). IHAT showed the higher prevalence of Toxoplasmosis (43.5% in sheep flowed by 31.8% in goats and 24.4% in camels) as compared with ELISA. On the other hand, ELISA showed the higher prevalence of Toxoplasmosis in sheep (45.9%) as compared with IHAT (43.5%). When the data from the IHAT was compared with that of the ELISA test, which was used as a reference test for toxoplasmosis, IHAT had the highest sensitivity (88.1%). It could be concluded that the IHAT and ELISA tests are efficient diagnostic tools for detection and selective diagnosis of Toxoplasmosis. Also high seroprevalence of Toxoplasma gondii in studied animals indicated the importance of these animals as the main source of human infection.