Freeway　toll　station　plays　an　important　role　in　Chinese　expressway　system,　and　the　construction　and　application　of　ETC　lane　has　become　more　and　more　widely.　Since　the　flow　of　ETC　lane　traffic　is　uninterrupted,　and　it　has　little　change　in　speed;　the　existing　queuing　theory　is　no　longer　fit　the　study　of　ETC　lane　traffic　capacity.　Meanwhile,　uninterrupted　traffic　flow　theory　cannot　describe　ETC　lane　traffic　characteristics.　By　field　observations　of　traffic　flow　characteristics　of　each　vehicle　type　in　ETC　lane,　unusual　vehicles　that　often　emerging　at　the　present　stage　is　classified　as　one　type.　This　paper　adopts　service　time　to　determine　its　passenger　car　equivalent　(PCE),　and　to　establish　ETC　lane　traffic　capacity　calculation　under　the　influence　of　unusual　vehicles　by　using　the　MGK　vehicle　queuing　model.　The　result　of　this　approach　can　provide　basis　of　ETC　lane　planning,　design　and　operational　management.　©　2012　American　Society　of　Civil　Engineering.