We report our initial experience in two patients using real-time three-dimensional echocardiography to assess perimembranous ventricular septal defect and device morphology and their relation with contiguous cardiac structure. Defect size and rims as well as device position and profile were displayed from the three-dimensional "en face" views. We think that real-time three-dimensional echocardiography could be a complementary approach to angiography and transesophageal echocardiography in performing transcatheter closure of perimembranous ventricular septal defect.