In the case of multiple trabecular ventricular septal defects, it is difficult to identify the exact locations and margins because of trabeculations of the right ventricle. It is also well known that ventriculotomy for closure of ventricular septal defects sometimes causes postoperative ventricular dysfunction or arrhythmia. To overcome these problems, we used the 'sandwich patch technique' to repair multiple trabecular ventricular septal defects.