Although　China　is　a　vegetable　planting　country,　the　degree　of　mechanization　of　vegetable　production　is　low.　With　the　advance　of　the　urbanization　and　industrialization　in　China,　arable　land　gradually　becomes　less,　and　the　vegetable　cultivation　is　paid　more　and　more　attention.　Facilities　vegetable　cultivation　is　an　important　way　for　vegetable　cultivation.　However,　the　level　of　mechanization　of　protected　vegetable　is　lower　than　25%,　and　the　comprehensive　mechanization　level　of　vegetable　production　is　about　20%,　while　production　of　leaf　vegetables　in　China　accounts　for　30%-40%　of　total　production.　Therefore,　the　development　of　efficient　and　stable　facilities　vegetable　harvesting　machinery　is　the　premise　to　achieve　the　automation　of　vegetable　plantation　and　production　process,　and　is　of　great　significance　to　achieve　the　mechanization　of　agriculture,　especially　vegetable　production.　However,　the　height　of　the　existing　vegetable　picking　machine　can　not　meet　the　requirements,　for　the　distance　of　the　rhizome　exposed　is　too　short,　which　leads　to　the　phenomenon　that　vegetable　is　cut　loose　and　harvesting　fails.　Therefore,　in　this　paper,　the　model　of　the　vegetable　harvester　is　established,　and　the　problem　of　cutting　is　analyzed.　Based　on　the　analysis　of　the　above　and　lower　parts　of　the　vegetable　stem　in　the　process　of　drawing,　the　mathematical　parameters　of　the　drawing　force　were　analyzed,　and　the　key　factors　affecting　the　pulling　force　of　the　vegetables　were　the　height　of　the　vegetables　and　the　height　slope.　Through　the　tensile　test　of　the　rhizome　of　the　vegetable　sample　and　the　compression　test　of　the　stem　of　the　vegetable　sample,　the　mechanics　parameters　of　the　vegetable　were　obtained,　and　the　necessary　theoretical　support　was　provided　for　the　simulation　of　the　drawing　of　the　vegetable　and　other　research.　The　distinct　element　method　(DEM)　is　a　numerical　simulation　method　for　dealing　with　discontinuous　medium　problems.　And　it　is　widely　used　in　the　field　of　bulk　material　processing.　EDEM　(enhanced　distinct　element　method)　software　is　a　general　CAE　(computer　aided　engineering)　analysis　software　based　on　the　DEM,　which　is　commonly　used　to　simulate　and　analyze　particle　processing　and　operating　system　in　industry　and　agricultural　production.　At　present,　its　application　in　crop　harvesting　has　not　been　reported,　but　it　has　been　successfully　applied　in　the　field　of　agriculture,　especially　in　the　treatment　of　soil　matrix.　The　discrete　element　simulation　model　of　vegetable　drawing　process　was　established　by　using　discrete　element　software　EDEM,　and　the　optimal　drawing　force　and　drawing　effect　were　determined　by　studying　the　mechanism　of　pulling　the　vegetables.　According　to　the　simulation　analysis,　the　relationship　between　the　pulling　force　of　vegetables　and　the　displacement　of　vegetables　and　the　simulation　process　of　vegetable　drawing　were　obtained.　It　was　determined　that　the　minimum　drawing　resistance　was　26.87　N　when　adopting　the　optimum　drawing　distance　of　20　mm.　The　maximum　safe　drawing　load　of　vegetable　rhizome　was　37.5　N　and　the　maximum　safe　compression　load　of　vegetable　stem　was　84.36　N　under　the　condition　of　safety　factor　of　1.1,　using　small　universal　testing　machine.　According　to　the　upper　and　lower　limits　of　the　drawing　force　and　the　mathematical　parameters　of　the　drawing,　the　inclination　angle　of　the　planting　trough,　which　met　the　requirement　of　planting　1-6　rows　of　vegetables,　was　determined　to　be　17.8°.　And　at　this　angle　of　inclination,　the　maximum　thrust　value　of　the　stem　of　the　vegetable　was　less　than　the　maximum　destructive　force　of　the　vegetable　84.36　N.　The　final　working　parameters　were　applied　to　the　single-row　prototype　test,　and　the　good　harvesting　effect　was　obtained,　which　verified　the　rationality　of　the　key　parameters　of　the　vegetable　harvester.　©　2017,　Editorial　Department　of　the　Transactions　of　the　Chinese　Society　of　Agricultural　Engineering.　All　right　reserved.