Objective To explore the clinical characteristics,therapy and prognosis of primary central nervous system lymphoma (PCNSL).Methods Forty-three PCNSL patients were retrospectively analyzed.Results The most frequent PCNSL clinical presentations were an increased intracranial pressure, focal neurologic deficits.The median survival time of patients was 18.0 months (14.2—21.8 months,95% CI).Cox regression model analysis revealed that ependymal and leptomeningeal involvement was the only independent factor for overall survival (P=0.002).Conclusions PCNSL is a aggressive disease with a poor prognosis and difficult to diagnose before operation.The optimal treatment modality for newly diagnosed PCNSL is still under investigation.