The current study aimed to determine the sero-prevalence of infection from four cities in kingdom of Saudi Arabia; Al Riyadh, Al Muzahmiah, Al Magmah and Asir. Samples were collected from October 2008 to April 2010. A total of 449 serum samples were collected from 3-6 years old sheep and goat suffered from late abortion. The obtained samples tested using an indirect enzyme linked immmunosorbant assay (ELISA). Three hundred forty five (76.84%) of  the all investigated samples were found to be positive, of which the heights ratios were 110 in Al Riyadh (33.56%) and Asir 130 (49.51%), while the lowest ratio was 45 (5.91%),                 60 (10.95%) in Al Muzahmiah and Al Magmah, respectively. To the author knowledge, this is the first report indicated the existence of Toxoplasma gondii among  small ruminants herds suffered from late abortion in KSA; so further investigations among other species to explore the potential for spread  and diagnosis of Toxoplasma gondii are recommended.