Endoscopic retrograde cholangiopancreatography (ERCP) is a technically challenging procedure. It takes time to learn the basic skill and at least 180 - 200 cases for trainees to achieve competency in ERCP. Hands-on practice in patients remains the gold standard for ERCP training. It required the trainer to stand by the trainee in the procedure room to assist. There were insufficient patients for most trainees to achieve competence until the trainee graduate. Technology-enabled health care at a distance has profound scientific potential and accordingly has been met with growing interest. We hypothesized that the trainee can be safely guided by a senior trainer off-site with the endoscopic view displayed on a screen. Using the teleguidance, the trainer can even continue to provide guidance when the trainees complete their training and return to their hospitals until they achieve the recommended clinical competency. Given the advantages of the off-site teleguidance, it could be an attractive substitute for hands-on assistance to ERCP training. The primary aim of this study was to evaluate whether off-site assistance (OA group) could achieve a comparable success rate to standard hands-on assistance (HA group) with regard to the rates of successful selective biliary cannulation during ERCP training.