Herein we describe the case of a patient with primary diffuse leptomeningeal gliomatosis (PDLG). After surgery and ventriculoperitoneal shunt placement, due to poor general conditions, the patient was not eligible for radiotherapy. For this reason we decided to start a systemic chemotherapy treatment with Temozolomide (150 mg/m2 per day for 5 days every 4 weeks). After three cycles a partial response was achieved with a clear improvement of general conditions. In our knowledge, this is the first time that PDLG treatment with Temozolomide has been described.