A case of double primary cancer of the esophagus and stomach with metastasis of the esophageal cancer to the stomach is reported. The entire stomach and the lower part of the esophagus were surgically resected and intrathoracic esophagojejunostomy was performed. Macroscopically, two tumors were found to be present, both in the lower esophagus and the stomach. There were two primary cancers, one a squamous cell carcinoma of the esophagus and the other a collision tumor of the stomach which consisted of well-differentiated adenocarcinoma and signet ring cell carcinoma. Furthermore, this collision tumor was present together with a metastatic lesion from the esophageal carcinoma.