Objective To access the left ventricular sysytolic function in children at acute stage of Kawasaki disease using speckle-tracing imaging. Methods Two-dimensional echocardiograghic images of 27 patients and 19 normals were collected in apical long-axis view, two-champer view, four-champer view, short-axis views at the levels of mitral annulus, papillary muscle and apex. The systolic peak values of longitudinal strain, radial strain and circumferential strain were measured by speckle-tracking imaging. Results Compared with controls the values of longitudinal strain and radial strain are lower in most segments in patients(P < 0.05). There were no significant differences between the patients and controls in circumferential strain(P>0.05). Longitudinal strain and radial strain measured were lower in 8 patients with coronary ectasia(including 7 cass with coronary artery aneurysms in vessels) than other 19 patients,but the two groups have no significant differences(P>0.05). Conclusions Long-axis and short-axis function of the heart decreased regardless of coronary artery ectasia.