The clinical value of three-dimensional time-of-flight magnetic resonance angiography(MRA)was retrospectively evaluated in 23 patients with arteriovenous malformations(AVM) in 8 and aneurysms in 15 cases. MR angiogram were compared with conventional angiogram(CA) in all cases. The topography of the AVM nidus and feeding artery were equally well appreciated on the MRA as on the conventional angiogram except one of nidus that was obscured by methemoglobin stated hematoma. Howevere, in four of 8 AVM, the draining veins were incompletely shown on MRA because of slow flow effect or out of field of view. In cases of aneuryms, all were equally depicted on MRA as on the conventional angiogram. But, the neck of aneurysm was more better shown on MRA than CA. MR angiography reliably depict intracranial vascular lesions, especially aneurysm and arteriovenous malformation.