S-1 adjuvant chemotherapy following radical surgery has been the standard therapy for the pStage II/III gastric cancer in Japan. However, there are few reports regarding treatment for gastric cancer recurrence during S-1 therapy. Here, we present a case of recurrent gastric cancer during S-1 adjuvant therapy that showed partial response to CDDP + capecitabine therapy. A 72-year-old man was diagnosed as having gastric cancer. We performed a distal gastrectomy+D2 dissection, with Roux-en Y reconstruction. The patient was treated with S-1 for adjuvant chemotherapy. Six months after operation, multiple mediastinal lymph node recurrence developed. CDDP + CPT-11 was applied for two courses as first-line treatment for the recurrence. However, the disease progressed with worsening mediastinal lymph node metastases (progressive disease). After two courses of CDDP + capecitabine as second-line chemotherapy, the recurrence site became smaller. After five courses, partial response (PR) had been achieved. Two years and five months after gastrectomy, capecitabine monotherapy was applied as third-line chemotherapy.