A 57-year-old woman had previously undergone a living-donor liver transplantation (LDLT) for end-stage liver disease related to hepatitis B virus. The liver graft had been donated by her husband. Her postoperative course had been uneventful. In the course of postoperative surveillance, she was incidentally found to have gastric cancer by an endoscopic examination 2 years after the liver transplantation. A gastric resection was the treatment choice, and the results were successful. The tumor, which was moderately differentiated adenocarcinoma, was limited to the mucosal layer, with no metastasis. In addition, a Helicobacter pylori infection was observed. This is the first reported case of a gastric cancer after LDLT. We report this case because of its importance regarding the need to carry out close surveillance in transplant recipients who are treated with immunosuppressive drugs, in order to make a timely identification of the occurrence of common malignancies.