The role of mycophenolate mofetil (MMF) has increased in the recent years, however its adverse effects on gastrointestinal system and bone marrow sometimes restrict its usage. The study was planned to investigate and compare the demographic features and clinical data of 173 renal transplant recipients receiving tacrolimus (TAC) with either 1 gram (group I, n=112 patients) or 2 grams of MMF (group II, n=61 patients), during a two-year period (January 2000-December 2002). Acute and chronic rejection episodes, patient and graft loss, posttransplant (post-tx) diabetes mellitus (DM) and hypertension (HT) rates were compared in these two groups. In both groups demographic features (age: 43±22 vs 41±21 years, gender: male/female: 71/41 vs 48/13, donor type: living-related/cadaveric: 57/55 vs 32/29) were similar. Also no statistical significance was observed in terms of acute (17/112 vs 12/61) or chronic (4/112 vs 1/61) rejection rates and 1st year and last serum creatinine levels (1.21±0.43vs 1.26±0.38, s1.3±0.61 vs 1.3±0.41 mg/dl, respectively). Post- tx DM and HT rates were similar in both groups. No patient death was observed in group I.The number of graft loss in group I was significantly lower than group II (3 vs 12, p<0.001). Chronic rejection (n=2) and recurrence (n=1) were the cause of graft loss in group I, while death (n=6; secondary to infection; CMV in 2, PTLD secondary to EBV in 1 and suicide in 1, cardiovascular event in 2 patients), primary nonfunction (n=2), recurrence of the primary disease (n=1), acute rejection (n=3) led to graft loss in group II. Kaplan-Meier survival analysis revealed that graft survival (1st year: 98%, 2nd year: 94% in group I and 1st year: 88%, 2nd year: 83 % in group II; LogRank: 0.005) and patient survival (1st year: 100%, 2nd year: 100% in group I and 1st year: 91%, 2nd year: 91 % in group II; LogRank: 0.001) rates were superior in group II. It is known that tacrolimus may diminish the glucronidation of mycophenoloic acid in the liver. Thus, in our patient group, using 1 g MMF seems to be safer and better choice with full- dose tacrolimus; regarding two-year graft and patient survival rates are concerned.