We had 4 cases with multiple ventricular septal defects (VSDs) in complexed congenital heart disease. One of four had two separate VSDs detected by two dimensional echocardiography before operation. Second of four had additional infundibular muscular VSD which was detected by echocardiography in the intensive care unit (ICU) after patch closure of a perimembranous VSD. The third case had two additional VSDs of inlet muscular and subaortic septum detected by transesophageal and direct echocardiography during reoperation, beside a subpulmonary VSD which was originally diagnosed before Jatene operation for double outlet right ventricle. The fourth case had multiple trabecular muscular VSDs diagnosed by postoperative angiography soon after Rastelli operation. Since these additional multiple VSDs compromise the postoperative hemodynamics if those are unrecognized, it is indispensable to detect all VSDs before operation, using transthoracic and transesophageal echocardiography.