Abstract: Objective To explore the role of intraoperative transesophageal echocardiography (TEE) in robotic perimembranous ventricular s eptal defect (VSD) repair. Methods A retrospective analysis was conducted with intraoperative TEE data of 18 consecutive patients who underwent robotic perimembranous VSD repair from January 2009 to August 2012. ① Before c ardiopulmonary bypass (CPB), TEE was performed to document the anatomic types, n umbers, and the size of VSD. The procedures were predetermined by the surgeon ac cording to TEE information. ② During the establishment of peripheral CPB, TEE w as used to guide the placement of cannulae in inferior vena cava (IVC), superior vena cava (SVC), and ascending aorta (AAO). ③ After weaning from CPB, TEE was conducted to evaluate the effect of the procedure. Results ① Accuracy of TEE was 100% for diagnosing the anatomic types of VSD. All the surgi cal procedures were performed based on the predetermined information. ② Under TEE guidance, all the cannulae in the SVC, IVC and AAO were located in correct p ositions. ③ In all patients, TEE confirmed successful VSD repair. Conc lusion TEE is a useful tool in the assessment of robotic perimembrano us VSD repair.