Endoscopic retrograde cholangiopancreatography (ERCP) has been widely used in diagnosis and treatment of pancreaticobiliary diseases. Traditionally, ERCP has been performed in the prone position. The prone position for ERCP can facilitate selective bile duct cannulation, offer a better fluoroscopic image of pancreaticobiliary anatomy, and prevent aspiration of gastric contents. However, in cases of difficult in the prone position, ERCP has been performed in the left lateral or supine position. Compared with the prone position, left lateral position is more comfortable for patients, especially with limitation for cervical movement including cervical cord injury, cervical spine operation, parkinson's disease, contracture due to cerebral infarction, and allow more easy passage of the scope through the pharynx, and useful to secure airway. However, in the left lateral position, it is difficult to obtain fluoroscopic image of right hepatic duct and intrahepatic bile duct.