A 56-year-old man with esophageal squamous carcinoma was found to have additional adenocarcinoma in the remnant stomach on the esophageal operation. He had undergone partial gastrectomy for gastric ulcer 30 years ago. He underwent transthoracic esophagectomy for esophageal carcinoma and remnant stomach resection for the remnant stomach carcinoma. After the course of supportive therapy, he succumbed to tumor recurrences 16 months after the operation. This is the first case of synchronous double carcinomas of the esophagus and the remnant stomach.