PURPOSE: Kawasaki disease is a systemic vasculitis, leading cause of pediatric acquired heart disease. Vascular endothelial growth factor (VEGF) has functions as vascular permeability factor, plays an important role in coronary artery lesion (CAL). We studied the clinical significance of serum VEGF in Kawasaki disease. METHODS: Kawasaki group was 49 patients, and control group was 15 patients. Diagnosis followed AHA (American Heart Association) diagnostic criteria, with blood sampling in acute, subacute, and convalescent phase. Echocardiographic abnormalities were defined and the definition of intravenous gamma globulin (IVGG)-responsive and IVGG-resistant was determined. RESULTS: Serum VEGF of Kawasaki group was significantly higher than of control group. Comparison of serum VEGF between CAL and non-CAL group, between carditis group and non-carditis group showed no significant differences. Subacute serum VEGF was statistically higher in IVGG-resistant group than in IVGG-responsive group, and serum VEGF of IVGG-resistant group in subacute phase was statistically higher than in the other phases. Serum VEGF of convalescent CAL and non-CAL group in acute and subacute phase had meaningful differences. Total fever duration and subacute serum VEGF had positive correlation. Acute serum VEGF had positive correlation with ESR and CRP, all phases serum VEGF had also positive correlation with WBC. Acute and subacute serum VEGF had negative correlations with hemoglobin and albumin. CONCLUSION: Serum VEGF can help to determine the severity of Kawasaki disease, especially subacute serum VEGF seems to be used as a prognostic factor of coronary complication. Afterward, further studies needed with more strict diagnostic criteria and more study groups.