Abstract: Discriminating the symptoms of vexing pain in Treatise on Cold Damage and Essentials from the Golden Cabinet， it was suggested that the pathogen of vexing painwas constraint of yang qi， either caused by wind-cold-dampness fettering the exterior， or sthenia of yang qi and cold blocking the exterior， or shaoyang inability to pivot， or interior heat accumulation caused by excessive yang heat， or steaming dampness-heat resulting in blockage of yang， or internal obstruction of cold-turbidity leading to failure of dispelling yang qi. The treatment should be based on specific causes and pathogenesis-constraint of yang qi. The treatment principle is dissipating excessive stagnation of fire.