Objective:To investigate the clinical effect of Daclizumab on preventing acute rejection in renal transplant recipients. Methods:71 patients were randomly divided into two groups:Daclizumab group(n =26) and control group(n = 45). Baseline regimen of mycophenolate mofetil(MMF), cyclosporin(CsA), methylprednisolone(MPD) and prednisone(Pred) were administered to all patients. The treatment of Daclizumab was based on baseline regimen. The Daclizumab group received Daclizumab twice before and after renal transplant. The occurrence of post-transplantation acute rejection, renal function and T lymphocyte subtypes were sequentially monitored; meanwhile adverse events, infection episode, and patient and graft survival were observed. All of patients received a follow-up of 12 months at least. Results:The occurrence of acute rejection in Daclizumab group in 1, 3, 6 and 12 months after renal transplantation was 7.7%, 19.2%, 23.1% and 30.8%, respectively,while it was 15.6%,28.9%, 35.6% and 46.7% in the control group. There was significant difference between the two group(P < 0.05). There was no difference in infection episodes and adverse events between the Daclizumab group and control group. One year patient survival was 92.3% in Daclizumab group, 91.1 % in control group(P > 0.05), compared with graft survival of 96.2 % and 93.3 % for Daclizumab and control group, respectively(P > 0. 05). The renal function in Daclizumab group in 1, 6 and 12 months after renal transplantation was better than that in control group(P < 0.05). The CD3+ and CD4+ subtypes decreased in both two groups after operation but no significant difference(P > 0.05). Conclusion:Daclizumab combined with MMF,CsA,MPD and Pred therapeutic regimen was effective to reduce the occurrence of acute rejection in renal transplant recipients and have no influence on T lymphocyte subtypes.