A 67-year-old man visited our hospital for epigastric pain. Esophagogastroduodenoscopy(EGD)revealed type 2 gastric cancer from the cardia to the gastric angle, and histopathological examination revealed papillary adenocarcinoma(pap), HER2-positive. Contrast-enhanced CT showed wall thickening mainly in the posterior wall of the gastric body, enlarged lymph nodes that were lumped together with the main lesion, and 8 low-absorption areas with ring shaped contrast effects in both lobes of the liver. The patient was diagnosed as gastric cancer cT4aN(+)M1[HEP], clinical Stage ⅣB. Six courses of capecitabine plus cisplatin plus trastuzumab(XP plus Tmab)therapy and 17 courses of capecitabine plus trastuzumab(X plus Tmab)therapy were performed. After chemotherapy, liver and lymph node metastases disappeared on CT and MRI. EGD showed residual gastric cancer, and the policy was to resect the primary tumor. Laparoscopic total gastrectomy with D2 lymph node dissection was performed. Pathological results showed T1b(SM)depth, no lymph node metastasis, and histologic response was Grade 2a. Six courses of X plus Tmab were administered as postoperative adjuvant chemotherapy, but were discontinued at the patient's request. Currently, 5 years have passed since the first chemotherapy and 3.5 years have passed since the surgery, and the patient is alive without recurrence, suggesting that the conversion surgery may have contributed to the prolonged survival.