Traffic　impact　studies　(TIS)　have　been　required　by　transportation　agencies　to　evaluate　the　potential　transportation　impacts　of　the　proposed　development　on　the　surrounding　neighborhood　since　2001　in　Beijing.　The　analysis　on　the　negative　aspect　brought　by　proposed　projects　in　terms　of　improper　location　and　excessive　number　of　driveways　or　inappropriate　opening　of　median　becomes　the　focus　of　TIS.　However,　the　analysis　of　the　traffic　conflicts　generated　by　proposed　development　has　been　so　far　limited　to　qualitative　interpretation　and　conflict　diagrams　in　traffic　impact　reports,　which　makes　it　difficult　for　traffic　professionals　to　evaluate　traffic　circulation　plans.　The　objective　of　this　paper　attempts　to　explore　to　quantify　traffic　conflicts　analysis.　Concept　of　conflict　complexity　is,　for　the　first　time,　introduced　in　this　study　as　a　new　evaluation　indicator.　The　model　to　estimate　conflict　complexity　is　then　built　up　by　putting　vehicle-bicycle　conflict,　vehicle-pedestrian　conflict　and　vehicle-vehicle　conflict　into　consideration.　This　indicator　can　be　used　to　quantitatively　determine　if　traffic　circulation　proposed　in　TIS　report　is　justified.　Finally,　based　on　the　data　from　65　TIS　reports　from　Beijing　city　the　threshold　values　for　criterion　are　determined　in　the　study.　The　result　from　this　study　will　help　transportation　agencies　make　decision　for　the　proposed　projects　in　quantitative　manner.　In　addition　it　can　also　pave　the　way　for　the　standardization　of　traffic　circulation　procedure.　(C)　2012　Published　by　Elsevier　B.V.　Selection　and/or　peer-review　under　responsibility　of　Beijing　Jiaotong　[BJU]　and　Systems　Engineering　Society　of　China　(SESC).