Surgical resection is not recommended. The principle of treatment is comprehensive, with high-dose methotrexate-based chemotherapy as the mainstay, which can be combined with rituximab, cytarabine, temozolomide, etc. Depending on the condition, radiotherapy can be used as treatment for chemotherapy-insensitive or relapsed/refractory PCNSL. The choice of radiotherapy regimen should be decided according to the site and size of the tumor, the patient’s age and physical function for evaluation.