Since　traffic　impact　study　(TIS)　of　projects　has　been　carried　out　in　Beijing　for　more　than　ten　years,　a　series　of　noticeable　results　have　been　achieved.　However,　there　are　still　some　unsolved　problems　in　TIS.　For　example,　there　is　a　lack　of　quantitative　analysis　of　traffic　organization　and　public　transportation.　The　objective　of　this　paper　is　to　attempt　to　develop　standards　of　traffic　impact　study　to　assist　the　government　in　developing　an　appropriate　evaluation　criterion　for　assessing　transportation　related　projects.　A　total　of　four　evaluation　indicators　have　been　selected.　The　four　evaluation　indicators　include:　variation　of　v/c　ratio,　complexity　of　conflict,　index　of　transit　capacity　and　satisfactory　degree　of　the　public　to　projects.　These　indicators　have　been　defined　and　modeled　in　quantitative　format　and　the　results　can　be　applied　in　the　evaluation　process.　©　2009　ASCE.