Some studies have found that the folic acid exerts a negative effect on lipid profile of ESRD patients, while others did not see any effect. We prospectively studied this effect in a population of renal transplanted patients. Patients with transplanted kidney who were under folic acid supplementation regimen were followed for a period of 4 months. The patients’ plasma levels of triglyceride (TG), LDL and HDL cholesterol were measured at baseline and then monthly after transplantation. We compared theses values using paired sample Ttest. The mean ± sd for baseline measure of folic acid, TG, HDL and LDL were 5.4 ± 3.1, 125.2 ± 41.3, 101.8 ± 29.8 and 60.9 ± 20.9 respectively. After 4 months, the plasma level of TG increased significantly and reached to188.4 ± 110 (p= 0.001). the baseline level of folic acid was significantly correlated with the change in plasma TG (r= 0.604, p= 0.001). patients with baseline folic acid of more than 6 mg/dl had significant change in their level of plasma TG (p = 0.011). The trend in LDL and HDL were increasing and decreasing, respectively (p>0.05). Folic acid caused a significant rise in TG level. Also, the trend in HDL and LDL level were towards the lipid profile disturbance. We conclude that with folic acid supplementation, probable late outcomes of lipid disturbance must be considered.