Objective:To discuss the application value of transesophageal echocardiography(TEE) in double-orifice technique for mitral valve insufficiency in children. Methods:From February 2006 to July 2009,22 patients underwent mitral valve repair using the double-orifice technique. All patients were examined by transthoracic echocardiography (TTE) preoperatively. During the whole procedure,the morphology,function,regurgitation of mitral valve and its affiliated structure were monitored continuously with TEE. The condition of valve was assessed with TEE again postoperatively. Results:In all cases,21 had a successful operation,and one had a second operation for severe regurgitation. All patients showed stable valve function,there were no stenosis of valve,no trans-valve pressure difference and no severe regurgitation. Conclusion:It was of very important clinical value to applicate TEE in double-orifice technique for mitral valve insufficiency in children,which was useful to improve the successful rate and reduce the complications,avoiding once more surgery.