Sjögren's syndrome(SjS)is a chronic systemic inflammatory autoimmune disease.Complement dysregulation plays an important role in the pathogenesis of SjS,and hypocomplementemia is closely related to the poor prognosis of SjS patients.However,the exact pathogenesis of complement dysregulation has not been fully elucidated.Based on the activation and regulation of the complement system,this review focuses on the current progress on the complement system in the pathogenesis of SjS,which will provide fundamental support for early diagnosis,disease activity monitoring,therapeutic intervention and prognosis assessment of SjS.