Public　Transportation　Priority　can　reduce　bus　delays　at　intersections,　effectively　ensure　the　punctuality　of　bus,　thereby　increasing　the　level　of　bus　service,　and　ease　the　city＇s　traffic　pressure　and　ensure　the　future　sustainable　development　of　the　city　of　great　significance.　Gray　evaluation　method　using　the　actual　running　state　of　the　traffic　signal　intersection　analysis,　analysis　and　comparison　of　import　Road　bus　lane　on　the　buses　before　and　after　setting　and　the　delayed　impact　of　other　social　vehicles,　and　the　results　with　the　theoretical　model　of　the　signal　intersection　delay　calculation　were　compared.　Simulation　results　show　that　the　gray　evaluation　method,　can　import　Road　bus　lane　signalized　intersection　before　and　after　the　delay　set　quantitative　evaluation,　and　has　good　maneuverability　and　practicality.　©　2011　ASCE.