Ankylosing spondylitis(AS) is one of the difficult and major diseases in clinical practice，and traditional Chinese medicine(TCM) has significant advantages in its treatment.However，there is still a lack of recognized criteria for syndrome diagnosis by now，which restricts the development，application，and promotion of TCM diagnosis and treatment plans for AS.Considering the above situation，an industry consensus on TCM syndrome standard was constructed by systematically integrating evidence-based medical evidence and expert clinical experience to provide a standardized basis for regulating TCM clinical diagnosis and treatment practice.Methods:Based on the Branch for Rheumatology of the Chinese Association of TCM chairman units，TCM experts were organized nationwide to construct a syndrome standard of AS by evidence-based medicine methodology.Based on relevant international standardized guidance，expert consensus development norms，and evidence-based medicine methodology，expert opinions were extensively integrated to form an expert consensus on TCM syndromes of AS by literature analysis，clinical investigations，and expert consultation.Results:Across the country，42 experts in various fields joined this consensus development.TCM syndrome types of AS were classified into five types：kidney deficiency，dampness-heat obstruction，liver-kidney deficiency，cold-dampness obstruction，and blood stasis obstruction syndromes.Consensus was reached on disease name，location，nature，syndrome characteristics，clinical differentiation，and prescription.Conclusion:Expert consensus on TCM syndromes of AS exhibits high credibility and authoritative degree，serving as a reliable reference for domestic and international colleagues in clinical practice and scientific research.