Based　on　extensive　study　of　the　traffic　demand　and　actual　situation　of　traffic　impact　analysis　in　Beijing,　this　paper　proposes　the　evaluation　criterion　for　traffic　impact　study.　Four　evaluation　indicators　are　involved,　which　include　variation　of　V/C　ratio,　complexity　of　conflict,　capacity　index　of　transit,　and　satisfactory　degree　of　the　public　to　projects.　It　implies　that　the　traffic　impact　from　project　construction　should　be　examined　in　terms　of　V/C　ratio　at　intersections,　traffic　organization,　public　transit,　and　traffic　conditions.　With　practical　operations,　the　evaluation　criterions　are　modeled　and　classified　according　to　quantificational　results.　The　impacts　from　projects　are　evaluated　and　defined　to　be　passed,　improvement　needed,　and　rejected.　The　study　provides　applicable　evaluation　criterion　for　the　quantificational　traffic　impact　analysis　in　Beijing.　©　2009　by　Science　Press.