A 91-year-old woman diagnosed to have an inoperable cholangiocarcinoma had an uncovered metal stent inserted for palliative drainage. About 1.5 years later, tumour ingrowth into the metal stent caused cholangitis. Intraductal radiofrequency ablation was applied to create local coagulative tumour necrosis and the necrotic tissue was removed via a balloon catheter. A plastic stent was inserted to empirically treat any ensuing potential bile duct injury. The patient was discharged without complication with good palliative drainage. Intraductal radiofrequency ablation is a new technique for the treatment of metal stent occlusion due to tumour ingrowths. This is the first case report of this relatively safe and feasible new technique for the treatment of tumour ingrowth into a metal stent used as palliation for malignant biliary obstruction.