The main role of thyroid hormones is to maintain normal brain growth during a critical period of life. Congenital hypothyroidism (CH) is one of the most common cause of mental retardation. In newborns, there are few symptoms, therefore, it is difficult to diagnose this disease. The objective of this study is to determine the prevalence of CH among neonates at the obstetrics and pediatrics hospital, Lattakia, Syria by screening all neonates born at this hospital. Out of 1760 neonates, 863 were males and 897 were females. The frequency of CH was 7/1760. The female: male ratio for CH was 2.5:1. Successful performance of congenital hypothyroidism screening program leads to the prevention of mental complications in affected children.