We report a case of advanced gastric cancer exhibiting the features of a submucosal tumor (SMT) of the gastric body. The patient was a 50-year-old male in whom a gastric SMT was detected during a mass screening examination. Upper gastrointestinal endoscopy revealed a protuberant tumor, 2 cm in diameter, covered with normal-appearing mucosa. Examination of an endoscopic biopsy specimen of the tumor revealed chronic gastritis with regenerative and erosive changes. An endoscopic ultrasound examination demonstrated a hypoechoic mass in the third layer of the gastric wall. The clinical diagnosis was gastric SMT, and the patient's course was monitored. Twenty-six months after the initial visit to our hospital, an endosonograph-guided biopsy revealed Group III (borderline lesion). Three months after the biopsy, the size of the SMT had increased slightly. Laparoscopic wedge resection of the tumor was performed to make a pathologic diagnosis and we were able to make a diagnosis of gastric lymphoepithelioma-like carcinoma intraoperatively. Gastrectomy with lymph node dissection was followed as curative surgery. Laparoscopic total excision biopsy is a useful technique in patients with a gastric SMT whose diagnosis has not been confirmed pathologically.