Objectives The objectives of this study were to assess the feasibility of preoperative gemcitabine/nab-paclitaxel-based chemoradiation therapy (CRT) for patients with borderline resectable pancreatic cancer (BRPC), which consists of induction chemotherapy and subsequent CRT, and to determine the recommended dose (RD) of gemcitabine/nab-paclitaxel with concurrent radiation therapy in a phase I trial. Methods Patients with BRPC received gemcitabine (1000 mg/m(2))/nab-paclitaxel (125 mg/m(2)) on days 1, 8, and 15 during each 4-week cycle, which was repeated for 2 cycles as induction chemotherapy. After induction chemotherapy, the patients received gemcitabine/nab-paclitaxel with concurrent radiation therapy. During CRT, the patients were scheduled to receive gemcitabine/nab-paclitaxel at 7 dose levels using a standard 3 + 3 dose escalation scheme. Radiation therapy was concurrently delivered at a total dose of 60 Gy. Results Thirty-eight patients initiated induction gemcitabine/nab-paclitaxel. Among these patients, 30 received subsequent gemcitabine/nab-paclitaxel-based CRT. The RD was determined to be level 5 (gemcitabine, 800 mg/m(2); nab-paclitaxel, 100 mg/m(2)). The dose-limiting toxicities included hematologic toxicity, infection, febrile neutropenia, and peripheral neuropathy. Twenty-four of 30 patients underwent pancreatectomy, and the R0 resection rate was 96%. Conclusions The RD of gemcitabine/nab-paclitaxel-based CRT after induction gemcitabine/nab-paclitaxel for patients with BRPC was 800 and 100 mg/m(2), respectively.