Microfluidic　chips　have　been　widely　used　in　various　of　areas,　such　as　biology,　chemistry,　medical　science　and　so　on.　As　one　of　the　key　techniques　of　microfluidic　chips,　the　technique　of　micro　driven　of　the　water　has　been　studied　by　experts　all　around　the　world　for　years.　Of　all　kinds　of　the　driven　methods,　the　power　costed　by　bionic　driven　is　lowest.　Moreover,　as　xylem　is　the　main　channel　to　transport　the　water　in　a　tree,　the　mechanism　of　water　transportation　has　been　always　an　important　issue　in　the　study　of　physiological　plant　ecology.　In　this　paper,　the　models　of　a　single　vessel　element　with　different　pit　numbers　(5　pits,　10　pits　and　20　pits)　or　diameters(4μm　and　7μm)　were　established　according　to　the　xylem　and　the　pits＇　structure.　The　3-dimensional　flow　distribution　was　analyzed　by　ANSYS　12.0　calculating　by　realizable　k-s　algorithm.　The　pressure　distribution　contours　and　the　velocity　distribution　contours　of　a　single　vessel　element　could　be　obtained　after　calculated　by　the　software.　According　to　the　results,　the　flow　field　in　a　single　vessel　element　of　the　xylem　was　studied.　In　addition,　the　influence　of　pits　on　the　pressure　and　velocity　were　analyzed.　The　results　showed　that　the　influence　on　pressure　and　velocity　is　less　when　the　diameter　is　smaller.　As　the　number　of　pits　on　the　vessel　increased,　the　influence　on　the　distribution　of　pressure　and　velocity　is　greater.　Based　on　the　result　of　numerical　simulation　of　vessel　element,　a　bionic　structural　microfluidic　chip　was　designed　and　then　analyzed　by　ANSYS　12.0.　©　(2015)　Trans　Tech　Publications,　Switzerland.