Abstract: Objective　To explore the potential role of endogenous vascular elastase (EVE) in pathogenesis of coronary artery lesions (CAL) in Kawasaki diseases (KD). Methods A total of 60 children with KD admitted from Jan. 2012 to Apr. 2013 were enrolled, and at the same time 60 febrile children with respiratory infection were enrolled as controls. The left and right coronary artery diameter value was measured by ultrasonic cardiogram. The levels of EVE, matrix metalloproteinases (MMP)-9 and transforming growth factor (TGF) -β1were determined by enzyme-linked immunosorbent assay and their correlations with coronary artery diameter were analyzed. Results The levels of EVE, MMP-9 and TGF-β1 in KD children in the acute phase were significantly higher than those in control group (P<0.01). Meanwhile, the level of EVE in KD children with coronary artery lesion (CAL) is significantly higher than that in KD children without CAL. The results of correlation analysis indicated that the levels of EVE, MMP-9 and TGF-β1 were positively correlated with coronary artery diameters (r=0.64~0.79, P<0.01). Conclusions EVE plays an important role in the CAL of KD may through inducing the produce of MMP-9, TGF-β1 and finally causing the formation of CAL.