Objective The aims of this study were to assess the developmental changes of coronary artery complications and Cardiac function in the murine model of Kawasaki disease (KD) With a high frequency ultrasound system and to provide evidence for preparation the murine model of KD. Methods Lactobacillus casei cell wall extract (LCWE) was prepared, and injected to C57BL/6 mice intraperitoneally to induce KD. Totally 40 mice were categorized into 2 groups randomly: KD model group and the control group with intraperitoneal injection of phosphate buffered solution, 20 mice in each group. On days 10, 21 and 60, the coronary artery dimensions were measured by echocardiography. Cardiac function including left ventricular end-diastolic diameter (LVIDd), left ventricular end-systolic diameter(LVIDs), ejection fraction(EF), fractional shortening(FS) and the blood flow velocity of atrioventricular valve during early diastole(E) /atrial contraction(A) were assessed. Results By echocardiography, the present study successfully detected coronary artery diameter and measured cardiac function in the murine model of KD. Two-dimensional echocardiography identified a high density echo images around the coronary artery wall at 10 days and 21 days following intraperitoneal injections of LCWE, and then, 4(20%) accompanied by local coronary artery aneurysm at 14 days and 21 days. The left coronary artery showed dilation in the murine model group of KD at 10 days and 21 days following LCWE injection. The diameter of left coronary artery in the murine model of KD（0.46?.11 mm on D10, 0.47?.09 mm on D21）was significantly higher than the control group（0.32?.14 mm on D 10, 0.36?.06 mm on D21, all P＜0.01). The right coronary artery diameter had no significantly differences among each groups（all P>0.05). In addition, there were no significantly differences in measurement of cardiac function including EF、FS、E/A、LV Vol d、LV Vol s、LVID d and LVID s among each groups at 10days, 21days and 60days following LCWE injection（all P>0.05）. Conclusions The present study successfully detected coronary arteries diameter and measured cardiac function by echocardiography in the murine model of KD. Our results suggested that the murine model of KD established by using an i.p. injection of L. casei cell wall extract was shown similar natural progression on coronary artery abnormalities with KD patient. Key words: Kawasaki disease; Model; Echocardiography；murine