Purpose To describe the demographic and clinical features and outcomes for children and adolescents with primary CNS lymphoma (PCNSL). Experimental Design A retrospective series of children and adolescents with PCNSL was assembled from ten cancer centers in three countries. Results Twenty-nine patients with a median age of 14 years were identified. Sixteen (55%) had Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≥ 1. Front line therapy consisted of chemotherapy (CT) only in twenty patients (69%), while 9 (31%) had CT plus cranial radiotherapy. Most patients received methotrexate (MTX)-based regimens. Overall response rate was 86% (CR 69%, PR 17%). The 2 year PFS and OS rates were 61% and 86%, respectively; the 3 year OS was 82%. Univariate analyses were conducted for age (≤ 14 vs > 14 years), PS (0 or 1 vs >1), deep brain lesions, MTX dose, primary treatment with CT alone, intrathecal chemotherapy and high-dose therapy. Primary treatment with CT alone was associated with better overall response rates with an OR of 0.125 (p=0.02). There was a marginally significant relationship between higher doses of MTX and response (OR =1.5, p = 0.06). ECOG-PS of 0–1 was the only factor associated with better outcome with hazard ratios of 0.136 (p = 0.017) and 0.073(p = 0.033) for PFS and OS, respectively. Conclusion This is the largest series collected of pediatric PCNSL. The outcome of children and adolescents appears to be better than in adults. PS of 0–1 is associated with better survival.