There are few treatment options for patients with non-Hodgkin lymphoma (NHL) who experienced progression after high-dose chemotherapy (HDC) with autologous stem cell transplantation (auto-SCT). The role of allogeneic stem cell transplantation (allo-SCT) in these patients has not been clarified yet. In this study, we report clinical outcomes of allo-SCT in patients with NHL who experienced progression after HDC with auto-SCT. Patients were enrolled from seven hospitals in Korea. A total of 38 patients were included: 18 patients (47.4%) underwent myeloablative conditioning and 20 patients (52.6%) reduced intensity conditioning. Overall response rate was 73.3%. Median event-free survival was 6.3 months. Median overall survival (OS) was 19.0 months. Estimated 5-year survival rate was 35.0%. Acute graft-versus-host disease developed in 13 patients (34.2%). Transplant-related mortality (TRM) was 21.1% (eight patients). Ann Arbor stage (p=0.022), performance status (p<0.001), and baseline serum albumin level (p=0.010) were significant risk factors for OS. Performance status (p=0.022) was a significant risk factor for TRM. Eight patients with persistent or progressive disease received donor lymphocyte infusion, and two of them achieved complete remission. In conclusion, despite high TRM, allo-SCT is a viable option for patients with NHL who underwent progression after HDC with auto-SCT.