Abstract： With reference to ancient classics on traditional Chinese medicine and modern medical literature，this article summarizes the origin and specific connotation of the theory of “left ascending and right descending”，explains the etiology and pathogenesis of migraine based on the theory，and explores the corresponding clinical treatment methods and selection of prescriptions and medicines. The theory is a high summary of the physiological functions of the liver and lung to promote the qi movement. On this basis，the etiology and pathogenesis of migraine can be divided into excessive or deficient left ascending and right descending，resulting in“pain due to blockage of qi and blood” and “pain due to deficiency of qi and blood”. In terms of treatment， the normal circulation of qi movement of the liver and lung can be restored by dispersing the evil externally，soothing the liver and regulating qi，pacifying the liver and down bearing counter flow or upraising the liver qi，or supplemented by medicines for promoting the compatibility of left ascending and right descending.