Current status and problems in diagnosis and surgical treatment for complicated cardiac anomalies were assessed by analyzing surgical cases consisted of 32 univentricular heart cases, 27 asplenia syndrome cases, and 8 polysplenia cases. Univentricular heart cases consisted of 3 cases of type A, 8 cases of type B and 21 cases of type C. All of 7 cases performed corrective surgery were with bidirectional cross blood flow. Corrective surgery was performed on 7 cases including 6 cases of ventricular septation procedure with blood flow conversion and a case of modified Fontan procedure, and 2 were survived. Anatomical corrective surgery was performed for complicated cardiac anomalies on 4 cases with asplenia syndrome and 7 cases with polysplenia syndrome, and 2 and 6 cases were survived respectively. It was possible to perform functional corrective surgery on some cases who had difficulties for anatomical corrective surgery. For anatomical corrective surgery, it is preferable to use left ventricle as systemic ventricle. In splenic dysgenesis cases, main causes of late deaths were infection (asplenia syndrome) and complete A-V block (polysplenia syndrome) and it is necessary to clarify the immune mechanism and conduction system of the heart.