An　airport＇s　terminal　curbside　is　a　passenger　transition　from　ground　transportation　to　air　transportation　or　vice　versa.　It　is　an　important　bottleneck　restricting　the　development　of　airports.　Reasonable　curbside　scaling　can　alleviate　serious　congestion　conditions　effectively.　This　paper　proposes　a　terminal　curbside　length　model,　and　then　takes　Beijing　capital　airport＇s　terminal　3　as　a　case　to　verify　the　effectiveness　of　the　model　after　analyzing　the　characteristic　of　traffic　flow.　Recommendations　of　terminal　curbside　lengths　under　different　traffic　condition　are　obtained　by　numerical　simulation.　The　model　makes　up　for　the　deficiency　of　the　design　method　of　airport＇s　terminal　curbside　and　provides　support　for　terminal＇s　curbside　geometric　design.