The patient, a 25-year-old woman, complained of epigastralgia. Her physical examination and routine laboratory data were unremarkable, though an upper G-I series and a gastro-endoscopy demonstrated a small sessile polypoid lesion at the posterior wall of the gastric body. An endoscopic biopsy specimen taken from the polyp revealed a typical carcinoid tumor. The patient underwent a wedge resection of the stomach and a sampling was taken of the regional lymph node around the left gastric vessels. Histologically, although the carcinoid tumor was 5 mm in diameter and limited to within the submucosal layer, it showed lymphatic and venous invasion into the submucosal layer and had metastasized to one of the regional lymph nodes around the left gastric vessels. Therefore, a total gastrectomy with an extended lymph node dissection was performed and no other metastatic lesion was uncovered. Of the reported cases with a gastric carcinoid thus far, none with a tumor size of less than 5 mm has evidenced metastasis. This case suggests that even cases of a minute gastric carcinoid should be treated by radical gastrectomy and extended lymph node dissection.