Objective:To analyse the role of Bcl-6/Blimp-1/IL-21 in pathogenesis of primary Sj?gren′s syndrome(PSS),the relationship between Bcl-6/Blimp-1/IL-21 expression and labial gland biopsy grading.Methods:Immunohistochemical(IHC) method was used to detect the expression of Bcl-6/Blimp-1 in salivary gland between 30 cases pations with PSS in disease group and 11 cases patients with mucous cyst,lower lip trauma in control group,and the serum IL-21 levels between disease group of 40 cases patients with PSS and 30 cases healthy volunteers were measured by enzyme-linked immunosorbent assay( ELISA) ,relations among 15 patients with IL-21 expression levels with labial gland biopsy grading.Results:The expression levels of Bcl-6/Blimp-1/IL-21 in disease group were higher than control group;in disease group,with pathological grades increased,the expression levels of Bcl-6/Blimp-1/IL-21 were also raised.Conclusion:①Bcl-6/Blimp-1/IL-21 may participate in the pathogenesis of PSS;Bcl-6/Blimp-1/IL-21 is associated with infiltration lymphocytes of salivary gland.