This phase II trial was conducted to evaluate the safety and efficacy of concurrent gemcitabine and high-intensity focused ultrasound (HIFU) therapy in patients with locally advanced pancreatic cancer. Patients with localized unresectable pancreatic adenocarcinoma in the head or body of the pancreas received gemcitabine (1000 mg/m) intravenously over 30 min on days 1, 8, and 15, and concurrent HIFU therapy on days 1, 3, and 5. The treatment was given every 28 days. Thirty-seven (94.9%) of the 39 patients were assessable for response, and two cases of complete response and 15 cases of partial response were confirmed, giving an overall response rate of 43.6% [95% confidence interval (CI), 28.0-59.2%]. The median follow-up period was 16.5 months (range: 8.0-28.5 months). The median time to progression and overall survival for all patients were 8.4 months (95% CI, 5.4-11.2 months) and 12.6 months (95% CI, 10.2-15.0 months), respectively. The estimates of overall survival at 12 and 24 months were 50.6% (95% CI, 36.7-64.5%) and 17.1% (95%CI, 5.9-28.3%), respectively. A total of 16.2% of patients experienced grade 3/4 neutropenia. Grade 3 thrombocytopaenia was documented in two (5.4%) patients. Grade 3 nausea/vomiting and diarrhea were observed in three (8.1%), and two (5.4%) patients, respectively. Grade 1 or 2 fever was detected in 70.3% of patients. Twenty-eight patients (71.8%) complained of abdominal pain consistent with tumor-related pain before HIFU therapy. Pain was relieved in 22 patients (78.6%). In conclusion, concurrent gemcitabine and HIFU is a tolerated treatment modality with promising activity in patients with previously untreated locally advanced pancreatic cancer.