Valve　transplantation　is　often　used　in　the　treatment　of　aortic　valve　insufficiency.　However,　after　surgery,　the　reconstructed　aortic　roots　have　an　expansion　phenomenon,　in　which　the　lack　of　valve　height　causes　the　aortic　valve　to　close　again.　In　this　paper,　the　effects　of　different　aortic　valve　height　design　on　valve　opening　and　closing　performance　were　studied.　The　optimal　surgical　plan　was　obtained　by　in　vitro　numerical　simulation,　providing　technical　support　and　theoretical　basis.　In　this　paper,　six　groups　of　three-dimensional　geometric　models　with　a　valve　height　increment　of　±　0.5　mm　were　established　with　a　root　diameter　of　26.0　mm　and　a　valve　height　of　14.0　mm.　Through　the　structural　mechanics　calculation　and　analysis　of　the　parameters　such　as　maximum　stress,　valve　area　and　contact　force　of　the　model,　reasonable　geometrical　dimensions　are　obtained.　The　study　found　that　the　maximum　stress　values　of　the　six　groups　of　models　ranged　from　640　to　690　kPa,　which　was　consistent　with　the　results　of　the　literature;　the　three-group　models　with　valve　heights　of　13.5　mm,　14.0　mm,　and　14.5　mm　were　within　a　reasonable　range.　The　contact　force　value　of　the　6　groups　of　leaflets　increased　with　the　increase　of　valve　height.　Studies　have　shown　that　the　height　of　the　aortic　valve　has　an　effect　on　the　aortic　valve　closure　performance.　A　valve　height　that　is　too　small　or　too　large　will　reduce　the　aortic　systolic　valve　area　and　affect　the　aortic　function.　Copyright　©　2019　by　Editorial　Office　of　Journal　of　Biomedical　Engineering.