There are very many causes of left vertebral artery occlusion, which must be judged according to the actual situation, of which the highest incidence is the factor of atherosclerosis, atherosclerosis is a natural process of the human body, with the age and the occurrence of hypertension, diabetes, hyperlipidemia, many people’s blood vessels will gradually produce narrowing eventually formed occlusion, etc., which is the most common factor. In chronic occlusion there are no clinical symptoms and the right vertebral artery can be compensated, so no special treatment is needed. There are also causes of vertebral artery occlusion that may be caused by trauma, such as head and neck trauma that may cause a vertebral artery entrapment, and the entrapment may sometimes produce acute occlusion, resulting in a variety of clinical symptoms that require early treatment. Vascular diseases such as vertebral artery may also appear aneurysm, aneurysm may also cause vertebral artery occlusion, autoimmune vascular inflammation is its own blood vessel itself appears certain abnormalities, and thus slowly develop eventually form occlusion, we need to improve the relevant examination to finally confirm the diagnosis.