This study aimed to analyze the overall survival period of adult lymphoblastic lymphoma patients treated with various therapeutic regimens, and to assess the determinants affecting survival outcome. Twenty-five adult patients with lymphoblastic lymphoma who had been treated at Severance Hospital, Yonsei University College of Medicine, Seoul, Korea from June 1996 to June 2005 were analyzed retrospectively. As an initial remission induction chemotherapy, the hyper-CVAD regimen was performed in eight patients, the Stanford/Northern California Oncology Group (NCOG) regimen in five, the CAVOP regimen in four, the m-BACOP regimen in three, and the CHOP regimen in one patient. Patients were divided into two groups according to their therapeutic modalities. Twenty patients received conventional chemotherapy alone and five received subsequent PBSCT after conventional chemotherapy. Four patients of the PBSCT group underwent autologous PBSCT and one underwent allogeneic PBSCT. The overall response rate was 80% (60% showing a complete response, 20% showing a partial response) and the relapse rate was 73.3%. The overall survival (OS) rate was 55.1% at 1 year, 31.5% at 5 years, and 23.6% at 9 years. The disease-free survival (DFS) rate was 46.7% at 1 year and 30.0% at 7 years. The 5-year OS rate in relation to the regimens was 60% with the Stanford/NCOG regimen, 50% with the CAVOP regimen, and 33.3% with the m-BACOP regimen. The patients treated with the hyper-CVAD regimen had an 18.2% 2-year OS rate, and other patients with CHOP or COPBLAM-V expired early in their course. The OS rate in patients treated with conventional chemotherapy alone was 19.8%, whereas patients treated with subsequent PBSCT after chemotherapy showed 50% overall survival (p=0.25). The age at presentation influenced the outcome of the patients (p=0.01). The Stanford/NCOG regimen is an effective initial choice of therapy for lymphoblastic lymphoma patients, and is superior to the hyper-CVAD regimen in complete response rate and overall survival rate (p =0.36). Addition of PBSCT after chemotherapy may be needed for achieving optimal outcomes.