We report two patients with Type 4 gastric cancers having multiple lymph node metastasis and carcinomatosa which responded well to TS-1. After administration of TS-1 orally for two courses, both patients showed improved extension of the gastric wall and almost complete reduction of metastatic lymph nodes. In case 2, colonic stenosis due to peritonum carcinomatosa disappeared after chemotherapy with TS-1. Total gastrectomy was performed in both patients in accordance with their wishes. It was confirmed histopathologically that TS-1 was effective against the primary sites and lymph node metastasis. Both patients are well without recurrence and continue taking TS-1.