This　paper　presents　a　simple　identifying　method　of　bike　group,then　takes　bicycle　groups　of　signalized　intersection　as　the　research　object,　investigations　and　video　cameras　are　carried　out　at　two　signalized　intersections　in　Beijing　and　Tianjin　city.　For　the　data　analysis,by　using　K-means　cluster　analysis　method,this　paper　selects　three　criterions　which　are　the　average　speed　of　bicycle　group,the　width　of　bicycle　group　and　the　length　of　bicycle　group.　Based　on　three　indexes,　the　passing　stage　of　the　bicycle　groups　at　two　signalized　intersections　of　Beijing　city　and　Tianjin　city　are　divided　into　three　stages　:the　first　stage　for　bicycle　group　gradually　spreading,the　second　stage　for　expanding,the　third　stage　for　gradually　shrinking.The　research　on　the　passing　stage　of　bicycle　group　starting　and　running　through　the　intersection　at　the　signalized　intersection　are　useful　for　determining　the　capacity　of　vehicles　with　the　impact　of　bicycle,　and　for　calculating　the　signal　timing　of　bicycle　under　the　mixed　traffic　flow　condition　at　signalized　intersection.　©　(2011)　Trans　Tech　Publications.