Abstract： Objective To explore the expression and significance intergrin alphavbeta3(art33)in the kidney of patients with IgA nephropathy(IgAN).Methods lmmunohistochemistry wag applied to detect the expression of avl33。fibronectin(Fn)and Connective tissue growth factor(CTGF)in the kidney of patients with IgAN.and correlation analysis was done with pathology and clinic index.Result With the development of the disease,the expression of etvl33 was gradually increased in the glomemlar capillary endothelial cell.and mesansial cell as well as glomerular crescent.The positive area ratio of αvβ33 in renal glomerulus was(16.18±o.98,19.58±0.99,28.35±1.99,17.72±2.17)％respectively in grade I～Ⅳ pathological changes.Among all the groups,the expression of αvβ33 was the strongest in grade Ⅲ,while decreased in grade Ⅳ(P<O.05).In grade I-Ⅲpathological changes,the expression of etv[33 in glomerulus had a positive correlation with IgA consistency in blood,the degree of proteinuria,sclerosed glomerular quantity,the expression of Fn in glomeru1us and CTGF in the renal interstitium.avg3 positive ratio Wag higher in Fibrinogen-related antigen(FRA)positive group and the group that lea or Fn deposited in the both Oomendar capillary wall and mesangial region,but estimated glomemlar filtration rate wag lower than that in other group(all P<0.05).Conclusion In renal tissue.IsAN αvβ3 Was correlated with the abnormal deposition of extracellular matrix and glomemlar sclerosis.The high expression of IgAN αvβ3 may indicate unfavorable prognosis.