Abstract: Ankylosing spondylitis (AS) is a chronic， progressive， autoimmune disease. In the past， treating AS generally aimed at regulating the kidney from the perspective of Traditional Chinese Medicine (TCM). However， based on the the latest study in modern medicine and the theory of interrelationship between generation and restriction， doctors of TCM regarded deficiency of kidney and asthenia of governor vessel as its pathogenesis， excessive dampness of spleen as its critical risk factor， and hold that its treatment thought should be focused on the theory of spleen-kidney axis and treatment method should be warming kidney， strengthening governor vessel， invigorating spleen and dispelling dampness. On this basis， the paper put forward Wenshen Jianpi Dingji decoction as the basic prescription.