Objective To compare the efficacy of three approaches of parallel-style bilateral metal stenting in the management of unresectable malignant hilar biliary obstruction. Methods Data of 118 patients with unresectable malignant hilar biliary obstruction (Bismuth type Ⅱ-Ⅳ) treated by endoscopic bilateral metal stenting in Oriental Hepatobiliary Surgery Hospital from January 2012 to February 2019 were retrospectively studied. According to the method of stent placement, patients were divided into three groups, both stents crossing the main duodenal papilla (long long-stent by stent, LL-SBS) group (53 cases), one stent crossing the papilla (long short-SBS, LS-SBS) group (53 cases) and no stent crossing the papilla (short short-SBS, SS-SBS) group (12 cases). The main outcomes, clinical success rate, stent patency, success rate of re-intervention of both intrahepatic systems and overall survival, were compared among the three groups. Results There were no significant differences in clinical success rate [96.2% (51/53), 98.1% (52/53), and 91.7% (11/12)], median stent patency [9.2 (8.0-10.3) months, 11.6 (6.8-16.4) months, and 8.1 (3.7-12.5) months] or overall survival time [6.7 (4.6-8.8) months, 7.6 (5.7-9.4) months, and 7.1 (0.7-13.6) months] among the three groups (all P>0.05). The success rate of endoscopic re-intervention of both intrahepatic systems was 12/13, 0/10, and 1/5 in LL-SBS, LS-SBS and SS-SBS groups, respectively (P<0.001). Conclusion Parallel-style bilateral metal stenting is an effective endoscopic modality in the treatment of malignant hilar biliary obstruction, and LL-SBS may improve the success rate of endoscopic re-intervention to both intrahepatic systems.