Background: Recent study has showed that selected patients with unresectable gastric cancer could benefit from surgical resection after achieving response following induction chemotherapy. We speculated that apatinib, an inhibitor of VEGFR-2, in combination with chemotherapy could increase response rate and resection rate following systemic therapy. This trial is designed to investigate the efficacy and safety of conversion surgery after apatinib plus S-1/oxaliplatin (SOX) for patients with unresectable gastric cancer (NCT03007446). Methods: This is a prospective, single-arm and open-label Phase II clinical trial. The primary outcome is resection rate after induction chemotherapy for patients with unresectable gastric cancer. The secondary outcomes include objective response rate and overall survival. Main eligibility criteria include patients with at least single non-curative factor confirmed by CT, MRI, PET-CT or staging laparoscopy: unresectable diseases with locally advanced gastric cancer (T4b); hepatic metastasis (H1; less than five lesions, total diameter ≤ 8 cm); peritoneal metastasis (CY1, P1). An estimated enrollment of 20 patients was planned. After receiving two cycles of apatinib (500 mg, oral, qd) plus SOX (S-1: 40mg bid, d1-14 q3W; oxaliplatin: 130 mg/m2, d1 q3W), patients will be subject to multidisciplinary team evaluation for surgery. First patients were enrolled in Dec 2016. Data analysis was planned in Nov 2018. Clinical trial information: NCT03007446