Objective. To evaluate the rejection, the chronic allograft nephropathy (CAN) and the delay in the function of the same (DGF) due to obesity and high BMI.Material and method. In this work, 500 patients of both sexes kidney transplant followed for 5 years were evaluated, post-transplant measurements of biochemical parameters and anthropometric measurements were made. It was also recognized data of chronic nephropathy and delayed graft function.Results: Five years after the transplant, there was an increase in BMI and an increase in the components of the metabolic profile: triglycerides, total cholesterol and hyperglycemia, as well as blood pressure. As a consequence we have also observed an increase in the incidence of chronic kidney disease and delayed graft function.Conclusion. Obesity significantly increases the incidence of post-transplant complications, which can finally be done through injection. An adequate control of BMI in kidney transplant recipients would directly influence long-term renal graft survival, which reduced the delay in allograft function, the appearance of CAN and prolonged renal allograft survival.