Background and objectives: Kidney transplantation is currently the treatment of choice for end-stage renal disease (ESRD). It should be strongly considered for all patients with ESRD with no contraindication to this operation. Renal allograft dysfunction has many etiologies. The greatest considerations are rejection, nephrotoxicity of calcineurin inhibitors, and recurrence of native kidney disease. This retrospective study aimed to review the causes of renal allograft dysfunction histologically and the possible associated factors. Methods: It was carried out on renal transplant recipients in King Fahd unit from January 2003 to January 2010 (147). The mean age was 28.18±12.24 years. As regard gender: 110 male and 37 female patients. Nearly 27% experienced at least one episode of renal allograft dysfunction. Results: Results revealed that the most frequent pathology encountered was acute active rejection (46.7%) while interstitial fibrosis with borderline rejection was the least frequent (5%). The results showed that increased donor’s age was proven to be an important factor. The type of pathology encountered was different according to the age of donors e.g chronic CsA effect and interstitial fibrosis occurred more in older donors (39±9.3, 45.3±6.3 respectively) than other types of pathological diagnosis. The time of allograft biopsy just after renal allograft dysfunction was significantly correlated with the type of pathology. As regard graft survival, 125 grafts (85%) survived for 48 months postoperatively and 22 grafts (15%) were lost. The main causes of graft loss were death of recipients with a functioning graft (68.1%).