Abstract: Objective：To discuss the clinical efficacy of biliary drainage with single pigtail plastic pancreatic stent after endoscopic retrograde cholangiopancreatography (ERCP) treating choledocholithiasis. Methods：Clinical data of 105 patients with common bile duct stones treated by ERCP from October 2014 to October 2016 in Shanghai East Hospital were analyzed retrospeoctively. These patients were divided into stenting group (n=38) and control group (n=67). The stenting group received ERCP＋endoscopic sphincterotomy (EST)/ endoscopic papillary balloon dilatation (EPBD)＋calculus removed ＋ single pigtail plastic pancreatic stent for biliary drainage，while the control group underwent ERCP＋EST/EPBD＋calculus removed＋ENBD. The incidences of post-ERCP acute pancreatitis（PEP）in the two groups were compared. The stent fall and dislodging in stenting group were observed. Results：The incidence of PEP was 13.1% (5/38) in stenting group and 14.9% (10/67) in control group. In the stenting group, 3 patients had stent dislodged on the first day after ERCP. One patient got stent removed from bile duct on the third day due to upper abdomen discomfort. The stents in 8 patients were removed successfully by endoscopy while they failed in self-releasing in 2 weeks. In the other 26 patients，without complications，the stents dislodged successfully and were excreted outside through the digestive tract. Conclusions：After ERCP treating choledocholithiasis，the application of single pigtail plastic pancreatic stent bile duct drainage can prevent the incidence of PEP, reduce the severity degree of PEP, and the stent can successfully dislodged without complications.