Mixed　traffic　is　one　of　the　most　remarkable　transportation　characteristics　in　Chinese　cities.　With　extensive　research　on　the　releasing　characteristics,　the　paper　presents　a　definition　of　the　two-stage　of　the　releasing　characteristic.　The　first　stage　is　that　the　pedestrians　and　bicycles　enter　the　crosswalk　in　the　form　of　conglomeration;　the　second　stage　is　that　the　pedestrians　and　bicycles　enter　the　crosswalks　stochastically.　The　variation　of　the　inner　structure　of　the　conglomeration　in　the　first　stage　of　green　time　is　analyzed,　and　a　method　of　＇suppositional　grids＇　is　presented　to　describe　the　conglomeration.　The　model　of　space　occupation　ratio　is　developed　to　describe　the　dynamic　movement　of　conglomeration.　Then,　the　characteristics　of　the　pedestrians　and　bicycles　are　illustrated　by　a　field　study.　A　time-space　chart　of　the　pedestrians　and　bicycles　is　extracted.　It　can　be　found　the　curve　is　dense　before　the　8th　second　of　the　green　time,　which　is　considered　as　the　first　stage　of　the　releasing　time,　and　the　following　green　time　is　regarded　as　the　second　stage.　Because　of　differences　of　the　velocities,　the　bicycles　usually　surpass　the　pedestrians　to　get　the　front　of　the　conglomeration.　Based　on　the　model　of　space　occupation　ratio,　the　space　occupation　ratio　of　the　conglomeration　is　observed　to　increase　first　and　decrease　then.　©　2010　China　Association　for　Science　and　Technology.