Abstract: Objective To study the efficacy and safety of double-channel endoscope in the diagnosis and treatment of low-level bile duct obstruction after Billroth Ⅱ subtotal gastrectomy. Methods A total of 67 cases of low-level bile duct obstruction after Billroth Ⅱ subtotal gastrectomy in our hospital between January,2013 and May,2015 were enrolled and randomly divided into observation group(33 cases)and control group(34 cases).The dual channel direct vision endoscopy was performed in the observation group,while traditional endoscopic treatment was performed in the control group.The curative effect,the level of serum total bilirubin(TBIL),alanine aminotransferase(ALT) and aspartate aminotransferase(AST),incidence of complication,and mortality during postoperative 6 months and 12 months were compared between the two groups. Results The total effective rate in the observation group was 87.88%(29/33),which was significantly higher than that of control group 64.71%(22/34,Z=-2.097,P<0.05);the serum total bilirubin(TBIL),alanine aminotransferase(ALT),aspartate aminotransferase(AST)levels were significantly lower than control group(t=4.235,4.482,4.401,P<0.05).The incidence of bleeding and intestinal perforation rate was 3.03% and 0.00% during the treatment in the observation group,which were significantly lower than those(20.59% and 14.71%)in the control group(χ²=4.910,5.244,P<0.05).The mortality rates in the observation group during 6 months and 12 month after the operation were 12.12% and 21.21%,respectively,which were significantly lower than 35.29% and 50% in the control group,the differences was statistically significant(χ²=4.947,6.057,P<0.05). Conclusion The effect of double-channel endoscope is distinct in the diagnosis and treatment of ow-level bile duct obstruction after Billroth Ⅱ subtotal gastrectomy.It can effectively ireduce the incidence of complications,prolong servial of patient,and worthy of clinical application.