3 cases of primary cerebral tumours associated to intracranial arterio-venous malformations are reported. The presenting symptoms were caused by the AVM in 2 patients, by the tumour in 1 patient. In 2 cases the lesions were coexistent, while in one case the tumour was diagnosed 30 months after resection of the AVM. The tumour was a glioma in 2 cases, a pituitary adenoma in 1 case. The AVM was located in the right hemisphere in 2 patients, and was always ipsilateral to the tumour. Surgical treatment was undertaken in all patients, and consisted of resection of the tumour and AVM in 2 cases, and only resection of the tumour in 1 case. As regards outcome, one patient survived with a mild deficit, and 2 patients died from the natural evolution of the malignant tumour. It is concluded that the management of associated AVMs and brain tumours should be decided in the individual patient according to various considerations, owing to the variability of each lesion and to the relatively benign prognosis of an arterio-venous malformation.