Intracranial three-dimensional time-of-flight (TOF) magnetic resonance (MR) angiography was performed in seven healthy volunteers and eight patients with both 1.5-T and 3.0-T MR systems with standard and high spatial resolutions (true voxel sizes, 0.48 x 0.75 x 2.00 mm and 0.30 x 0.44 x 1.00 mm, respectively). Superior image quality and significantly better depiction of small vessel segments and vascular disease were observed at high-spatial-resolution 3.0-T TOF MR angiography but not at standard 1.5-T or standard 3.0-T TOF MR angiography (P <.01, respectively). Intracranial high-spatial-resolution TOF MR angiography at 3.0-T imaging provides diagnostic improvement in studies of cerebrovascular disease.