Stomach cancer can occur during chronic inflammation from Helicobacter pylori (HP) infection, and its occurrence can be suppressed by eradication of HP. However, the effects of suppressing stomach cancer by HP eradication are limited, and the cancer is known to recur even after eradication of this infection. Here, we report the case of a 56-year-old male patient with gastric cancer who, although undergoing HP eradication after treatment of early gastric cancer with endoscopy, experienced five metachronous cancer recurrences over a period of 13 years. Whether observation of patients who undergo eradication of HP due to peptic ulcers or chronic gastritis and patients who undergo eradication after endoscopic treatment for early gastric cancer should be performed at the same interval is an issue that must be addressed in the future. The appropriate observation period for each patient must be established while considering the burdens to the patient and from the medical economic perspective.