Blood　coagulation　is　a　complex　physiological　process.　With　the　development　of　biochemistry　and　molecular　biology,　especially　the　discovery　of　the　tissue　factor　pathway　inhibitor　(TFPI)　and　further　research,　the　researches　of　tissue　factor　(TF)　and　TFPI　have　been　the　hot　topics　now.　Based　on　this　result,　we　provide　a　new　concept　of　blood　coagulation　system　and　provide　a　dynamic　model　to　describe　the　role　of　TFPI　of　this　pathway.　Through　stability　analysis　of　the　equilibrium　point　and　numerical　simulations,　we　obtain　some　important　conclusions.　All　these　results　may　have　great　significance　for　lesions　of　cardiac　vessels　and　cerebral　vessels,　haemophilia,　DIC,　thrombosis　formation　and　malignancy.　(c)　2005　Published　by　Elsevier　Ltd.