Abstract: Objective To discuss adequate application of mycophenolate mofetil (MMF) in hepatitis C patients after kidney transplantation. Method A one-year follow-up study was conducted in 49 patients with hepatitis C but normal liver function before kidney transplantation, who were given postoperatively immunosuppressants of predisone, MMF and CsA/FK506. Patients with abnormal liver function after kidney transplantation who continued MMF therapy at routine dose and those with reduced or suspended MMF therapy all received intravenous therapy for liver protection, and the duration of therapies was recorded. Results Nineteen patients presented with abnormal liver function after operation, and the duration of abnormal liver function till recovery was 32.82±4.13 days in the patients with unsuspended MMF therapy and 13.31±2.98 days in those with reduced or suspended MMF (P<0.05); the former patients required subsequently 62.7±3.23 days to recover normal liver function and the latter need only 23.4±2.29 days (P<0.05). Conclusion MMF should be reduced or suspended when liver function abnormality occurred in patients with hepatitis C after kidney transplantation, and immediate intravenous therapy for liver protection may prove beneficial.