The microsurgical anatonry around the osigin of the ophthalmic artery was CAamined under disscting microscope in 42 heads (80 sides). The ophthalmic artery arose from the anteromedial or superomedial aspect of the sipraclinoid potion of the internal carotid artery in 92.5% In one case the artery was originated from the middle meningeal artery, The originating portion of the ophthalmic arteres was under the optic never in 88% The ophthalmic artered the orbits through the optic canal(96.3%) and eniered the optic canal at the subdural space (68.8%) or the epidural space(27.5%) The average length from the faciform fold of dura mater to the pertorating point of dura mater by ophthalmic artery was 4.0㎜/ and from the point of origen of the artery was 4.4㎜ The average angle between course of the ophthclmic artery and sagittal plane was 52˚ The mean dismeter of the ophthalmic artery was 1.7㎜(range 0.8-2.7㎜) The main trunk of the ophthalmic artery ran onder optic-nerve in 11 cases (13.9%)