Age is an important prognostic factor in acute childhood lymphoblastic leukemia (ALL): intermediate age children (1-9 years) show a better outcome than infants (0-1 year) and adolescents (10-15 years). However recent literature data do not agree about adolescents worse prognosis. We tried to contribute to this issue with a retrospective analysis about presenting features and survival of 302 pediatric patients (65 adolescents and 237 children) with non B ALL enrolled on AIEOP protocols at the Departments of Pediatric Haematology-Oncology (University of Turin) from 1976 to 1992. The last follow up was 30.11.94. We found in adolescents, in spite of higher frequency of unfavourable prognostic factors (Hb > 8 g/dl, mediastinal mass, T cell immunophenotype, L2 morphology), an event free survival similar to children (EFS 52% vs 51%). In conclusion in our population we found that age at diagnosis greater than 10 years does not represent an unfavorable prognostic factor.