OBJECTIVE: With the progression of the renal insufficiency (RI) produced in the chronic allograft nephropathy (CAN), the patients´ HRQoL worsens. The treatment of the anemia associated to the RI with rh-EPO improves the HRQoL. The objective of present study was to evaluate the HRQoL of kidney transplant patients with CAN and anemia associated to the RI, and the effect of the treatment with rh-EPO on the HRQoL. METHODS: Prospective study of 24 kidney transplant patients with RI caused by CAD and anemia who received rh-EPO to treated the anemia. The hemoglobin target was 12 gr/dL. HRQoL was evaluated with the SF-36 Health Survey at start treatment, 3 months later and at the end of follow-up. SF-36 scores (8 dimensions, Physical-PCS and Mental Component Summary-MCS) were standardized by age and gender using the Spanish general population norms. The "Effect Size" was also calculated for each dimension and for summary scores. RESULTS: Hemoglobin statistically improved from start to third month (p <0.01). SF-36 scores of studied patients were worse than those of the general population and that those of a transversal sample of transplant patients with good renal function: PCS = 36.08±12.83 vs 48.68±9.86; MCS = 47.16±14.46 vs 51.91±10.25. Three SF-36 dimensions statistically improved with the correction of anemia with the rh-EPO treatment: Role Physical, Vitality and Mental Health. The "Effect Size" was very small for Physical Functioning and Social Functioning; small for General Health (0.28) and PCS (0.23); moderate for Pain (0.41), Role Emotional (0.39) and MCS (0.42); and large for Role Physical (0.65), Vitality (0.81) and Mental Health (0.74). CONCLUSIONS: The poor HRQoL of kidney transplant patients with CAN and anemia improves with the treatment of the anemia with rh-EPO. The "Effect Size" for this change in the HRQoL is moderate to large in majority of HRQoL areas.