A 10-year-old girl with heart murmur immediately after birth was found to have a ventricular septal defect (VSD). Although she had been followed up for an insignificant shunt, funnel chest became apparent and was referred to our hostpital at the age of 10. She was 133 cm in height, 25.7 kg in weight with a body surface area of 0.99 m². The VSD was the muscular outflow type with a Qp/Qs of 1.1, defect of 2.5 mm in diameter, and pulmonary artery pressure of 24/10/15 mmHg. Pectus excavatum was apparent with a CT index of 2.99. The preceding surgery for one was likely to interfere with the subsequent surgery for the other. Therefore we decided on concomitant surgery for both. Under median sternotomy, cardiopulmonary bypass was established and the VSD was closed with a patch. After the pericardium was sutured and closed, a tape was carefully passed through the chest wall under the guidance of direct vision and digital palpation. A metal bar was inserted guided by the tape, reversed with a rotator, appropriately shaped with a hand bender, and was fixed to the chest wall with the stabilizer bars at both ends. The sternum was sutured with 1-0 polyester sutures and two sternum pins made of particulate hydroxyapatite and poly-L lactide. The postoperative course was uneventful. After 2 years, the excavatum was adequately corrected and the bar was successfully removed under general anesthesia. Although the comorbidity of VSD and funnel chest is rare, concomitant surgery for both can be safely carried out and may be considered as an option for treatment.