The　transmission　capacity　of　Mobile　Ad　Hoc　Networks(MANET)　is　constrained　by　the　mutual　interference　of　concurrent　transmissions　between　nodes.　At　first,　we　study　the　transmission　capacity　of　MANET　by　the　view　of　information　flow　between　nodes.　At　the　same　time,　we　also　study　the　problem　that　the　interference　between　nodes　effect　on　the　transmission　capacity　of　MANET　by　the　tool　of　the　event　conflict　graph.　Secondly,　the　paper　presents　the　method　to　compute　the　maximum　expectant　achievable　capacity　for　the　given　conflict　graph.　We　conclude　and　prove　an　sufficient　condition　that　the　information　flow　transmit　successfully　between　nodes.　At　last,　we　simulate　the　results　and　give　a　fitting　equation　of　transmission　capacity　between　nodes.　©　2006　IEEE.