Endoscopic ultrasonography (EUS)-guided biliary drainage was performed for treatment of patients who have obstructive jaundice in cases of failed endoscopic retrograde cholangiopancreatography (ERCP). In the present study,we introduced the feasibility and outcome of EUS-guided choledochoduodenostomy in four patients who failed in ERCP. We performed the procedure in 2 papilla of Vater,including one resectable case,and 2 cases of cancer of the head of pancreas. Using a curved linear array echoendoscope,a 19 G needle or a needle knife was punctured transduodenally into the bile duct under EUS visualization. Using a biliary catheter for dilation,or papillary balloon dilator,a 7-Fr plastic stent was inserted through the choledochoduodenostomy site into the extrahepatic bile duct. In 3 (75%) of 4 cases,an indwelling plastic stent was placed,and in one case in which the stent could not be advanced into the bile duct,a naso-biliary drainage tube was placed instead. In all cases,the obstructive jaundice rapidly improved after the procedure. Focal peritonitis and bleeding not requiring blood transfusion was seen in one case. In this case,pancreatoduodenectomy was performed and the surgical findings revealed severe adhesion around the choledochoduodenostomy site. Although further studies and development of devices are mandatory,EUS-guided choledochoduodenostomy appears to be an effective alternative to ERCP in selected cases. Endoscopic ultrasonography (EUS) -guided biliary drainage was performed for treatment of patients who have obstructive jaundice in cases of failed endoscopic retrograde cholangiopancreatography (ERCP). In the present study, we introduced the feasibility and outcome of EUS-guided choledochoduodenostomy in four patients who failed in ERCP. We performed the procedure in 2 papilla of Vater, including one resectable case, and 2 cases of cancer of the head of pancreas. Using a curved linear array echoendoscope, a 19 G needle or a needle knife was punctured transduodenally into the bile duct under EUS visualization. Using a biliary catheter for dilation, or orbillary balloon dilator, a 7-Fr plastic stent was inserted through the choledochoduodenostomy site into the extrahepatic bile duct. In 3 (75%) of 4 cases, an indwelling plastic stent was placed, and in one case in which the stent could not be advanced into the bile duct, a naso-biliary drainage tube was placed instead. In all cases, the obstructive jaundice rapidly improved after the procedure. Focal peritonitis and bleeding not requiring blood transfusion was seen in one case. In this case, pancreatoduodenectomy was performed and the surgical findings revealed severe adhesion around the choledochoduodenostomy site. Yet further studies and development of devices are mandatory, EUS-guided choledochoduodenostomy appears to be an effective alternative to ERCP in selected cases.