We performed a retrospective multicentre analysis to study the clinical features and treatment outcomes of B-lymphoblastic lymphoma (B-LBL) and T-lymphoblastic lymphoma (T-LBL) in Asian adult patients, and identify risk factors that predict relapse and poor prognosis. Fifty-five newly diagnosed patients (45 T-LBL and 10 B-LBL) were analysed. All patients were treated with intensive chemotherapy regimens including VPDL (vincristine, prednisolone, daunorubicin, L-asparaginase), CALGB (Cancer and leukemia group B), and Stanford/Northern California Oncology Group (NCOG). There was no difference of clinical features between B- and T-LBL except the frequent site of involvement. The overall response rate including complete response (28/55, 50.9%) and partial response (18/55, 32.7%) was 83.6%. Among 46 responders, 22 patients relapsed leading to 20 deaths. Partial responders showed more frequent relapse (10/18, 55.6%) than complete responders (11/28, 39.2%). The median progression-free survival (PFS) was 17 months (95% confidence interval, 11.5-22.5), and the 2-year overall survival was 52 ± 7% with a median follow-up of 50 months (range 8-152). Treatment outcome of T-LBL and B-LBL was not significantly different in terms of response and survival. The presence of pleural effusion was significantly prognostic for overall and PFS (p < 0.05). In conclusion, clinical features and treatment outcome of Asian adult LBL were comparable to previous results, and the prognosis is still poor despite intensive chemotherapy.