We present a rare case of cardiac surgery for coronary artery single vessel disease and aortic valve stenosis after substernal gastric interposition for gastric cancer. An 80-year-old man, who had undergone esophagectomy and substernal gastric interposition 7 years previously, was referred to our institute for surgical treatment of coronary artery disease and aortic valve stenosis. Through a median sternotomy with cardiopulmonary bypass, we performed aortic valve replacement and coronary artery bypass grafting to the right coronary artery without injury to the gastric tube. Postoperatively, the patient was on respirator care and catecholeamine support for several days. Although urinary tract infection occurred, he recovered with antibiotic therapy. Finally, he was discharged on postoperative day 40. For cardiac surgery after substernal gastric interposition for esophageal cancer, even though the substernal gastric tube may preclude the usual median approach, median sternotomy is an appropriate alternative with close preoperative examination and careful dissection of substernal gastric tube.