Many patients suffering from breast carcinoma have metastases at initial diagnosis. The common metastatic sites are skeleton, liver and lung. Metastases to stomach are rare and only three cases have been reported in Korea. The endoscopic features of gastric metastases from breast carcinoma can be divided into three main categories: diffuse infiltration, external compression, and localized tumor deposition with ulceration or with a polypoid mass. However, metastatic gastric lesions which resemble early gastric carcinoma are rare. Typically, gastric metastases are confined to submucosa and muscularis, so that mucosal biopsy specimens might be false-negative. We report a case of gastric metastasis from infiltrative lobular carcinoma of the breast in a 66-year-old woman who had undergone left mastectomy with postoperative radiotherapy 17 years earlier. Initial diagnosis was early gastric carcinoma, signet ring cell type on gastric biopsy findings. However, definitive diagnosis of metastatic breast cancer was confirmed after endoscopic mucosal resection of a presumed primary early gastric carcinoma.