Abstract: Spontaneous external carotid artery compensation for ischemic moyamoya disease (MMD) as a bypass or compensatory blood supply pathway during progressive stenosis at the terminal portion of the internal carotid artery, plays an extremely important role in cerebral tissue perfusion and has a positive effect on the prognosis of patients with ischemic cerebrovascular disease. In recent years, there are many studies on external carotid artery compensation in MMD. This article summarizes the relevant studies on spontaneous external carotid artery compensation in ischemic MMD, providing a research basis for further clarifying the initiation and proliferation mechanism of compensatory vessels.