Objective: To investigate the clinicopathological characteristics of primary central nervous system lymphomas (PCNSL). Methods: The clinicopathological data of 26 patients with PCNSL diagnosed in Shanghai General Hospital from 2013 to 2020 were collected and analyzed by light microscopy, immunohistochemistry and in situ hybridization. Results: All patients were pathologically confirmed by biopsy or resection. Limb movement disorder was the most common symptom, and cerebral hemisphere was most frequently involved. Twenty-four patients had diffuse large B-cell lymphoma with B cell markers expressed by immunohistochemistry, and the remaining 2 patients had lymphomatoid granulomatosis (LYG), with EBER negative, and non-specific peripheral T-cell lymphoma (PTCL-NOS) with EBER positive. Seventeen patients were followed up for 1–8 years, of which 6 survived and 11 died, with survival ranging from 1 to 30 months. Conclusion: PCNSL is rare and lacks specificity in clinical features. Diagnosis depends on pathology to distinguish it from glioma, metastasis, and infection. Non-GCB type DLBCL is relatively common and has a worse prognosis, which requires further optimization of the treatment plan under the condition of clear pathological classification.