In　China,　road　traffic　carbon　emissions　and　their　share　in　total　carbon　emissions　have　significantly　increased.　In　the　context　of　double　carbon,　the　Beijing-Tianjin-Hebei　region,　the　largest　urban　agglomeration　in　northern　China,　is　receiving　more　and　more　attention.　Due　to　the　unbalanced　development　in　Beijing-Tianjin-Hebei　urban　agglomeration,　this　thesis　presents　three　computational　models　to　calculate　road　traffic　carbon　emissions　for　large,　medium-sized,　and　small　cities　and　intercity　traffic　arteries　based　on　the　road　network.　The　results　show　that　in　2019,　Beijing　has　the　highest　road　carbon　emissions　reaching　19.91　million　t　CO2　which　is　almost　three　times　that　of　Shijiazhuang,　the　capital　city　of　Hebei　province.　Dwellers＇　commuting　usually　results　in　an　increase　of　2.9%,　3.3%,　and　4.5%　on　weekdays　compared　with　weekends　for　Tianjin,　Shijiazhuang,　and　Beijing,　respectively.　As　for　the　intercity　road,　the　daily　traffic　flow　is　about　1.92　million　vehicles,　leading　to　total　carbon　emissions　of　22.97　million　t　CO2.　In　addition,　the　reduction　potential　of　carbon　emissions　in　Beijing　is　evaluated.　If　the　average　road　speed　is　increased　to　0.9V(f)　(road　design　speed)　during　the　morning　rush　hour　in　Beijing　from　7　a.m.　to　8　a.m.,　the　road　emission　reduction　could　reach　57.85%.