Objective: To observe the effects on proliferation and apoptosis in human umbilieal vein endothelial cells (HUVECs) cultured with the serum of the children with coronary artery lesions of Kawasaki disease, in order to further understand the possible mechanism of vascular endothelial injury from Kawasaki disease. Methods: HUVECs were cultured and divided into 4 groups, including the normal serum group, the general fever group, the non-CALs group, and the CALs group. The proliferation was detected by MTT test and the apoptosis was detected by flow cytometry (FCM). Results: The OD value of the HUVECs detected by MTT test after being cultured with the serum of the children with Kawasaki disease including the Non-CALs group and the CALs group (0.492±0.033 and 0.395±0.031, respectively) were lower than that of the general fever group and the normal serum group (0.592±0.033 and 0.612±0.036, respectively) (P<0.01). The apoptosis of HUVECs detected by FCM after being cultured with the serum of the children with Kawasaki disease was higher than that of the other two groups (P<0.01), and the apoptosis of CALs group was higher than that of the Non-CALs group. Conclusion: The serum from children with coronary artery lesions of Kawasaki disease could inhibit the proliferation of HUVECs and induce the apoptosis。