Among 1,420 patients with thoracic esophageal carcinoma, 85 (6.1%) had synchronous gastric carcinoma. Seventy-two patients (84.7%) underwent esophagectomy. Their operative mortality and prognosis were similar to those without gastric carcinoma. Among them, 25 patients, of whom the majority had advanced gastric carcinoma, underwent transthoracic esophagectomy with total gastrectomy (group A); eight died of esophageal cancer and four of gastric cancer. Forty-six patients, of whom the majority had gastric carcinoma in an early stage, underwent esophagectomy and esophagogastric anastomosis following partial gastrectomy or local treatment for gastric carcinoma (group B). None of the group B patients had recurrent gastric carcinoma. The operative burden was larger in group A. The 5-year survival rate for groups A and B were 38.8% and 23.0%, respectively. Esophagectomy and esophagogastric anastomosis after limited treatment for gastric carcinoma is an adequate treatment for the majority. However, esophagectomy and total gastrectomy are recommended for patients with advanced gastric carcinoma.