Objective　 To explore the values of transesophageal echocardiography in determining optimal depth of insertion of CVP catheter in infants undergoing cardiovascular surgery.　Methods　100 infants underwent cardiovascular surgery were selected in this study. The CVP catheterization was performed under the guide of TEE. The position of the catheter tip determined by AP chest x-ray, was identified by the level of thoracic vertebra(T) corresponding to the position of the catheter tip.　Results　The position of tip normally distributed from T4-T6 which anatomically corresponded to SVC under the guide of TEE. Conclusions　TEE is a simple and accurate guide for positioning the catheter tip at the level of T4-T6 in infants.