Local recurrences often develop after the resection of bile duct cancer. Imaging modalities do not have sufficient sensitivity or specificity to enable the definite diagnosis of recurrent bile duct cancer, and it may be difficult to decide when to start chemotherapeutic treatment. It is difficult to obtain specimens by conventional endoscopy after Roux-Y biliary reconstruction. The double-balloon endoscope(DBE) has 2 balloons: one at the tip of the endoscope and the other at the over- tube. The 2 balloons are inflated alternately and the endoscope can move through the small intestine in a caterpillar-like manner. DBE simplifies the approach to Roux-Y choledochojejunostomy and to obtaining a pathological specimen. Moreover, endoscopic biliary drainage and cholangiography can be performed with the DBE. Recently, the DBE has enabled systemic chemotherapy to be started after obtaining pathological evidence of malignancy, as well as biliary drainage instead of percutaneous transhepatic biliary drainage in cases with recurrent bile duct cancers. Here, we present 3 cases of recurrent bile duct cancer diagnosed and treated by a DBE.