This　paper　proposes　several　evaluation　indexes　for　road-network　operation　conditions,　including　the　average　speed　of　area　road　networks　for　different　land　use,　the　ratio　of　congestion　on　the　road-section,　the　reliability　coefficient　of　travel　time,　and　the　travel　time　of　unit　mileage.　Based　on　the　historical　traffic　data　gathered　from　the　Beijing　Floating　Car　Data　(FCD)　collection　system,　this　paper　presents　the　comprehensive　evaluation　and　the　comparison　analysis　of　the　road　network　operation　states　in　four　stages,　which　were　the　stage　before　the　Olympic　Games,　the　stage　during　the　2008　Beijing　Olympic　Games,　the　first　stage　of　tail　number　limit　and　the　second　stage　of　vehicle　restriction　for　the　two　tail　numbers.　The　research　indicated　that　the　average　speeds　in　peak　hours　had　significant　improvements　in　the　central　urban　area　of　Beijing.　The　average　travel　speed　of　the　road　network　increased　about　25-30　during　the　stage　of　the　odd-even　number　limit　than　that　without　TDM　policy.　Similarly,　the　average　travel　speed　in　the　first　stage　of　tail　number　limits　had　been　enhanced　approximately　15,　while　10　enhancement　had　occurred　during　the　second　stage　of　tail　number　limits.　©　2010　ASCE.