We retrospectively reviewed the medical records of 45 patients with relapsed acute leukemia after initial allogeneic hematopoietic stem cell transplantation (allo-HSCT). Among 45 patients, a total of 11 patients eventually underwent second allo-HSCT (HSCT-2). Median survival after relapse was 294 days (range, 135-942 days) for HSCT-2. Multivariate analysis showed significantly better survival for recipients of second allo-HSCT than for other patients (hazard ratio, 4.38; 95 % confidence interval, 1.45-13.2; P = 0.009). Although outcomes for patients with relapsed leukemia were generally poor, our results suggest that second HSCT could offer a survival advantage over other conventional salvage strategies.