We herein report a case in which preoperative chemotherapy with cisplatin and 5-fluorouracil was found to effectively treat far advanced gastric cancer invading the pancreas forming a huge mass with regional and distant lymph node metastases. As a result of this treatment regimen, a potentially curative resection was performed which led to a substantially increased survival. The patient was treated with 10 mg of cisplatin and 1000 mg of 5-fluouracil each day preoperatively. After the continuous administration of these drugs for 28 days, the findings of extensive pancreas invasion and lymph node metastases dramatically disappeared. The tumor could be curatively resected by a total gastrectomy with lymph nodes dissection, combined with a distal pancreatectomy and splenectomy. A histological study of a resected specimen showed some cancer cell infiltration remaining within the muscularis propria with fibrous change. There was no evidence of either pancreas invasion or lymph node metastasis. As a result, postoperative adjuvant chemotherapy was performed, 14 months later lymph nodes recurrence was detected and the patient died 20 months after surgery. Our findings suggest that preoperative chemotherapy may thus be effective for the treatment of gastric cancer by both reducing the tumor burden and prolonging survival.