Immunosuppressive therapy enhances the development of atherosclerosis by increasing lipid levels especially in first 3-6 months. We compared the effects of azathioprine (AZA) and MMF combined with steroids and cyclosporin A (CycA) in the first year after renal transplantation. We included 97 renal transplant patients (71M/26F; age: 34.7±13.1 years, renal transplantation duration: 44.9±12.9 months). AZA-CycA-prednisolone was used in 26 patients and MMF-CycA-prednisolone in 71 patients. Doses were AZA 150 mg/day, MMF 2 g/day, prednisolon 10 mg/day and CycA was given to maintain blood levels between 200-300 ng/dl. Serum lipid levels (total cholesterol, triglyceride, HDL, LDL, VLDL) were checked from the initiation of drug therapy with 3 month intervals for 1 year. Cholesterol and triglyceride levels increased during the study period(p=0.001 and p=0.02 respectively) but there were no significant difference between the groups(p>0.05). No difference was present in HDL, LDL, VLDL levels during the study period and between the groups(p>0.05 for all). In conclusion, although serum lipid levels tend to increase during CycA and steroid therapy in renal transplant patients, MMF and azathioprine have no advantage on each other regarding the effects on lipid profile.