More　and　more　bifurcation　tunnel　structure　forms　are　used　in　the　construction　of　urban　underground　tunnel　projects.　Tunnel　traffic　characteristics　change　with　the　change　of　the　tunnel　structure,　and　the　pollutant　emission　and　diffusion　will　also　change　in　the　tunnel.　In　order　to　grasp　the　traffic　characteristics,　the　dynamic　vehicles　emission　and　the　distribution　characteristics　of　traffic　velocity　and　pollutants　concentration,　the　research　team　conducted　a　survey　on　four　typical　urban　tunnels　in　China　during　2011-2015　through　status　survey　and　field　measurement.　The　survey　includes　traffic　characteristics　(traffic　flow,　average　speed),　vehicle　emission　characteristics,　CO　and　NOx　concentration　distribution　characteristics　in　the　tunnel.　The　result　can　provide　a　quantitative　assessment　method　to　support　pollutant　concentration　ventilation　control　and　energy　saving　operation　in　urban　bifurcate　tunnel.