A five-year-old boy with a univentricular heart, inferior vena cava interruption, and azygos connection was admitted to our hospital to undergo a staged Fontan-type procedure. Pectus excavatum had developed after he underwent total cavopulmonary shunt at the age of three years. Computed tomography revealed that the hepatic vein was just behind the recessed sternum. We performed simultaneous Nuss and Fontan-type procedures because we were afraid of the compression of the Fontan pathway from the hepatic vein to the pulmonary artery by the recessed sternum. A cardiopulmonary bypass was established and the hepatic vein and pulmonary artery were bypassed with a 16-mm expanded polytetrafluoroethylene graft. After removing the cardiopulmonary bypass, the Nuss procedure was performed. Although the bilateral thoracic cavities were diffusely and densely adhered, adhesiotomy was safely performed under direct visualization. The postoperative course was uneventful. Postoperative computed tomography showed that the pectus excavatum was well repaired and the Fontan pathway was not compressed by the sternum. Although there are few reports of Fontan-type and Nuss procedures being simultaneously performed, this method is useful for securing the space of the Fontan pathway and for preserving good Fontan circulation in the long term.