Plexiform vascular networks of the rete mirabile in humans are rare but can be observed in some vertebrates such as cobaye, cat, cow and sheep. Each set of embryonic arteries can be a potential source of these vascular networks which reconstitute the distal flows in segmental agenesis of internal carotid or vertebral arteries especially in patients with PHACE (posterior fossa malformation of the brain, facial hemangiomas, arterial anomalies, cardiac anomalies with coarctation of aorta, and eye abnormalities) syndrome. Ophthalmic rete mirabile has been found in some mammals such as camel, deer and avian species of pigeon, Hawaiian seabirds and deep-water fish of the cod other than human. We describe the first human case of ophthalmic rete mirabile confirmed on angiography in a patient with moyamoya disease. These findings are the first description in the English literature as far as we know. The clinical implications with moyamoya disease will be briefly discussed according to the embryologic development of cranial arteries.