The aim of this study is to evaluate the role of monoclonal antibodies (DACLIZUMAB) in early and late kidney graft survival and prevention of graft loss, compared with the group who did not receive Daclizumab. 57 kidney transplanted patients enrolled in this study, who were admitted and transplanted in Kidney Transplantation Unit, Sina Center ,Tehran, since April 2007 to March 2008. Preoperatively, all were received induction protocol (oral prednisolone+ mycophenolate mofetil+ cyclosporine-A). 23 patients were injected 1 mg/kg daclizumab (within 24 hours before, and 14days after transplantation). The evidence of delayed graft function(DGF), acute rejections, therapeutic pulse prednisolone ,or anti-thymocyte globulin(ATG), CMV infection ,episodes of UTI, early graft function (on discharge creatinine), and late graft function(6-16 months postoperatively) were evaluated between two groups. SPSS version 16 software and t-test were used as statistic method for analysis. The age range in injected group was (18-61 years) ,and in non injected group was(13-60 years). The evidence of DGF was 4% vs.3%, reversible acute rejections was 34%vs.14.5%, irreversible acute rejections was 0% vs.9%(p-value<0.05) in injected and non injected groups respectively. Therapeutic ATG used in 21% vs 23%, and pulse prednisolone 26% vs.20% respectively. The range and mean creatinine on discharge (early graft function) was (0.9-4) 1.4 mg/dl vs. (0.5-3.5) 1.35 mg/dl, while the last (6-16 months) creatinine was (1-2) 1.35 mg/dl vs.0.5-2.7) 1.2 mg/dl ,and the highest creatinine level through this period (1-2.7) 1.76 mg/dl vs. (1.1-3) 1.74 mg/dl in injected and non injected group respectively.the evidence of CMV infection was 30% vs35%, and UTI was 17% vs. 19%. Prophylactic injection of Daclizumab has an effective role in improvement of early graft survival and prevention of irreversible acute rejection also can help to make acute rejection amenable for therapy and cure. To evaluate the real role in long term survival, extended posttransplantation followup is needed.