Aortic　dissection　is　a　common　disease　which　is　very　dangerous,　with　high　mortality　rate.　Bypass　graft　for　the　treatment　of　DeBakey　III　dissection　has　outstanding　advantages　than　the　ordinary　replacement　of　thoracic　aorta,　and　some　patients　will　inevitably　require　the　use　of　the　procedure.　The　purpose　of　this　study　was　to　explore　the　impact　of　the　subclavian　artery-abdominal　aorta　bypass　graft　on　hemodynamic　parameters　in　the　false　lumen　and　the　effectiveness　of　surgical　treatment.　First　of　all,　the　idealized　three-dimensional　geometric　models　of　DeBakey　III　aortic　dissection　and　its　subclavian　artery-abdominal　aorta　bypass　graft　operation　were　constructed,　respectively.　Then　the　models　were　imported　into　ANSYS　11.0　for　finite　element　analysis.　Results　of　numerical　simulation　showed　that　both　velocity　and　pressure　of　the　blood　flow　were　reduced　after　bypass　graft　at　the　entrance　and　in　the　internal　sac　of　false　lumen,　which　is　very　favorable　for　reducing　the　impact　of　blood　flow　on　false　lumen,　slowing　down　the　further　expansion　of　entrance,　preventing　the　breakdown　of　false　lumen,　and　promoting　the　healing　of　dissection.　Therefore,　the　subclavian　artery-abdominal　aorta　bypass　graft　operation　is　an　effective　surgical　method　for　the　treatment　of　DeBakey　III　aortic　dissection　in　some　particular　cases.　This　operation　is　with　great　prospects　for　clinical　application.