The authors report the first adult case of pleomorphic xanthoastrocytoma associated with neurofibromatosis-1. A 40-year-old man with history of neurofibromatosis-1 underwent total removal of a right temporo-parietal superficial glioma followed by radiation therapy. Eighteen years after surgery, the patient remained well with no tumour recurrence, which prompted review of the surgical material. The diagnosis of pleomorphic xanthoastrocytoma was then made though the tumour exhibited malignant features histologically, with marked necrosis.This extremely good clinical outcome suggest that some astrocytoma tumours in patients with neurofibromatosis might be associated with a favourable prognosis.