Objective Endoscopic gallbladder stenting (EGBS) is an alternative treatment option for high-risk surgical patients with acute cholecystitis. However, there are no reports focusing on EGBS in patients with concomitant unresectable cancer. The aim of this study was thus to evaluate EGBS in such patients. Methods Twenty-two consecutive patients with acute cholecystitis and unresectable cancer were enrolled between September 2010 and December 2014. Their median age was 74.5 years (range: 51-95). Thirteen patients were men and nine were women. The primary cancers of the patients were biliary tract cancer (9), pancreas cancer (9), lung cancer (2), gastric cancer (1), and colon cancer (1). The causes of cholecystitis were calculus cholecystitis (7), obstruction by malignant tumor (13), and obstruction by fully covered stent (2). Results EGBS was successfully performed in 17 patients (77.2%). The technical success rates for calculus cholecystitis, obstruction by malignant tumor, and obstruction by fully covered stent were 85.7% (6/7), 69.2% (9/13), and 100% (2/2), respectively. No complications were observed. Percutaneous transhepatic gallbladder drainage was conducted on two patients in whom EGBS had failed and then we performed EGBS by a rendezvous approach. Of the 19 patients in whom we finally deployed EGBS, the median follow-up period was 229 days (range: 14-880 days). A recurrence of acute cholecystitis occurred in three (15.7%) patients 14, 130, and 440 days after EGBS placement. The rates of recurrence of cholecystitis at one and two years were 10.5% and 18.7%, respectively. Conclusion Our study demonstrated that EGBS is a safe and effective method for acute cholecystitis in patients with concomitant unresectable cancer.