Hyperhomocysteinemia is emerging as an independent predictor of cardiovascular disease and hypertension among children. The aim of the study was to examine the effects of oral folic acid on homocysteine and blood pressure. Folic acid supplementation has been found to reduce homocysteine levels and in some cases blood pressure. Five hundred and twenty children participated in the study, and 26 of them were found to be hyperhomocysteinemic; 20 of these children randomly received 5 mg oral folic acid supplement while the other six children were the controls. Serum homocysteine (P < 0.001) levels as well as systolic (P < 0.001) and diastolic (P = 0.045) blood pressure were statistically significantly decreased in the intervention group compared with the controls, while folic acid levels were statistically significantly increased (P < 0.001). Total serum homocysteine levels were correlated with age, serum folate, body mass index, and blood pressure. It appears that folic acid may be a safe and effective supplement to reduce homocysteine and possibly blood pressure, which consequently may prevent cardiovascular disease in children in early life.