The study tries to investigate the effect of renal transplantation on the life quality of dialyzed patients in Urmia. As prospective study needs a long time so the study was carried out case-controlly on 80 dialyzed and 80 transplanted patients randomly. The material of the study was a questionnaire including personal characteristics, type of disease and life quality in three different areas of physical, psychological and social relationships. The questionnaire was validitated by doing a=0.9466 Cronbakh. The questionnaire was filled by doing interview.From all the 152 patients, 9% reported their quality of life as bad, 44.9% as moderate and 46.2% as good. In the dialyzed group the percentage was as the following: 56.8% as bad, 40.5% as moderate and 2.7% as good. The mean of transplanted patients was 3.47 by 0.736 standard diviation. It was 2.23 by the standard diviation of 0.489 for the dialyzed group. The difference between the two was significant (P<0.0005). It is concluded that by doing transplantation, the life quality of dialyzed patients would improve. So it is strongly suggested that by doing cultural programms, the people should be persuaded to present their kidneys in case of serious brain damage. The spritual and humaniterian sides of thee presenting a kidney must be emphasized too. In that case it is not necessary for dialyzed patients, to wait long for transplantation. Kidney transplantation will increase Quality of Life in these patients.