From April 1983 to August 1991, 70 cases of Kawasaki disease were admitted to Taiwan Provincial Tao-Yuan General Hospital. Fifty-seven patients treated with aspirin 80-100 mg/kg/day alone during the acute phase were followed by two-dimensional echocardiography for two weeks to two years. Twelve cases (21%) complicated with coronary arterial aneurysm (CAA) were referred as high risk group. Those who had no CAA were a low risk group. Stepwise discriminant analysis was performed to obtain risk factors of CAA based on clinical and early laboratory data. This yielded a classification accuracy of 75.4%. The combination of two parameters, white blood cell count and C-reactive protein, can be applied to early identify Kawasaki patients at high or low risk of CAA.