The efficacy of high-dose chemotherapy followed by autologous hematopoietic SCT for relapsed diffuse large B-cell lymphoma (DLBCL) has been reported, but an optimal conditioning regimen has not been determined. This study was conducted to evaluate the safety and efficacy of the MCVAC regimen (consisting of ranimustine (MCNU), cytarabine, etoposide and CY) followed by autologous peripheral blood stem cell transplantation (PBSCT) for patients with high-risk or relapsed DLBCL. A total of 40 patients with DLBCL who received the MCVAC regimen followed by autologous PBSCT were retrospectively evaluated. Median follow-up duration of the surviving patients was 51.2 months (range, 5.4-151.2 months). At 5-year OS and PFS were 73.7% (95% confidence interval (CI), 58.6-88.8) and 62.5% (95% CI, 46.8-78.2), respectively. Although relapse remained the most frequent cause of treatment failure, late-onset adverse events were observed, including two cases of severe pulmonary impairment, and two cases of therapyrelated myelodysplastic syndromes (MDS)/AML. In conclusion, the MCVAC regimen would be an effective and tolerable conditioning regimen without TBI for autologous PBSCT for high-risk or relapsed DLBCL. However, late-onset pulmonary toxicity and MDS/AML should be monitored.