目的　统计分析肝外胆管的血供来源和分布以及在十二指肠上段胆管的吻合动脉链之间的多环形血管网，为胆管外科手术提供临床解剖学理论依据。  方法　以丙烯酸树脂为动脉填充剂灌注6例肝外胆管动脉制备铸型标本，使用photoshop测量法测量微小血管内径，观测和分析肝外胆管的血供来源和分布情况。  结果　肝固有动脉左、右支在肝总管上方存在弓型交通支，十二指肠上段胆管左右边缘的吻合动脉链间有丰富的横向动脉，吻合动脉链的供血约53%来自下方，来自上方的约占46%，1%来自中段肝固有动脉。通过对每条横向动脉中部的内径和两侧起始部的内径测量，发现肝总管中段和上段的横向动脉较粗，中部的平均内径分别为（0.26±0.02）mm和（0.24±0.04）mm，与两侧的内径比也比较大，上段比值最大，为1.09，中段其次，为1，下段中部的平均内径为（0.14±0.03）mm；与两侧的内径比值为0.74。  结论　肝外胆管上、下方的血供来源比例相对均衡；肝外胆管手术应尽可能于动脉吻合相对较少的胆总管十二指肠上段和血管相对较细小肝总管下部做纵行小切口，以降低肝外胆管血供的损伤；肝总管段的血供丰富,支持现行原位肝移植离断部位在胆囊管汇合处上方的主张。

Objective　The micro-arterial cast specimens of extrahepatic bile duct were used to elucidate the source and distribution of extrahepatic bile duct blood supply and the characteristics of multiple annular vascular networks between the anastomosis artery chains of the upper duodenal bile duct, providing a clinical anatomical basis for biliary surgery.　Methods　Six cases of extrahepatic bile duct arteries were injected with acrylic resin as arterial filler. Photoshop was used to measure the inner diameter of small blood vessels. The blood supply source and distribution of extrahepatic bile duct were observed and analyzed.  Results  The left and right branches of the proper hepatic artery had arcuate communicating branches above the hepatic duct. There were abundant transverse arteries between the anastomotic artery chains at the left and right edges of the upper duodenal bile duct. The blood supply of anastomotic arterial chain was about 53% from the bottom, 46% from the top and 1% from the middle hepatic artery. Through the measurement of the diameter of the middle segment of each transverse artery and the initial diameter of both sides, it was found that the middle and upper segments of the  transverse arteries of the hepatic duct were larger, with an average middle diameter of （0.26±0.02）mm and（0.24±0.04）mm, respectively. The ratio of inner diameter of the upper segment to the middle segment was 1.09. The ratio of the middle segment to the middle segment was 1. The average inner diameter of the middle part of the lower segment was（0.14±0.03）mm. The ratio of inner diameter to both sides was 0.74.　Conclusions　The blood supply at the upper and lower ends is relatively balanced. In order to alleviate the injury of extrahepatic bile duct blood supply, a small longitudinal incision should be made in the upper part of the duodenum of the common bile duct and the lower part of the small common hepatic duct with less arterial anastomosis as far as possible. The blood supply of the common hepatic duct is abundant, supporting the current proposition that the isolated site of orthotopic liver transplantation is above the confluence of the gallbladder.