A two-dimensional echocardiographic examination was conducted on 184 patients with Kawasaki disease iteratively from the acute phase to the convalescent phase. Aneurysms or dilatation of the coronary arteries were observed in 37 patients (20.1%). Among these 37 patients, 22 had persistent abnormality even after eight weeks from the onset. In the remaining 15 patients, abnormal findings disappeared within eight weeks. Coronary angiography was performed on all of these 37 patients and compared with the findings of echocardiography. In consequence, echocardiographic findings were concordant with those of the angiography in 35 patients. Therefore, the two-dimensional echocardiographic examination is thought to be a reliable noninvasive method for evaluating the coronary arterial lesions of Kawasaki disease in the acute phase.