In patients with malignant biliary obstruction, endoscopic placement of biliary stents offers similar technical success rates. Endoscopic retrograde cholangiography (ERCP)-guided stent placement has become the preferred approach to palliate malignant biliary obstruction. The major mechanisms of self-expandable metallic stent (SEMS) occlusion are tumor ingrowth, tumor overgrowth, and epithelial hyperplasia. These mechanisms provide the rationale for developing a drug-eluting stent in order to improve stent patency. Limited data exist regarding outcomes of paclitaxel-eluting stents in malignant biliary obstruction. This study is to prospectively compare the effectiveness and safety of paclitaxel-eluting covered metal stent and covered metal stent for the treatment of malignant biliary obstruction.