Abstract： AIM To evaluate the efficacy of negative pressure nasobiliary drainage in the management of acute obstructive cholangitis after endoscopic retrograde cholangiopancreatography (ERCP).METHODS One hundred and eighty patients with acute obstructive cholangitis treated by ERCP were randomly divided into a control group and an experimental group.The control group was treated by conventional endoscopic nasobiliary drainage (ENBD),while the experimental group was treated by ENBD with continuous negative pressure.The efficacy and safety were then compared between the two groups.RESULTS There was no significant difference in gender,age,or underlying disease between the two groups (P ＞ 0.05).All cases were operated successfully.The total amounts of biliary drainage at 24 h,48 h,and 72 h after ERCP were significantly higher in the experimental group than in the control group (P ＜ 0.05).The levels of serum total bilirubin and direct bilirubin at 24 h and 72 h after ERCP were significantly lower in the experimental group than in the control group (P ＜ 0.05).The levels of C-reactive protein,procalitonin,TNF-α,and IL-10 at 24 h and 72 h after ERCP in patients without post-ERCP pancreatitis (PEP) and hyperamylasemia were significantly lower in the experimental group than in the control group (P ＜ 0.05).The levels of serum amylase at 2 h and 24 h after ERCP were significantly lower in the experimental group than in the control group (P ＜ 0.05).The incidence rates of PEP and hyperamylasemia in the experimental group (6.67％,6/90;10％,9/90) were significantly lower than those in the control group (11.1％,10/90;17.18％,16/90) (P ＜ 0.05).Severe PEP did not occur in either group.CONCLUSION ENBD with negative pressure suction in patients with acute obstructive cholangitis after ERCP can effectively alleviate cholangitis and reduce the incidence of PEP and hyperamylasemia.