This　study　establishes　eight　emission　scenarios　in　the　air　pollutant　emissions　inventory　of　Chengdu　City,　China.　We　use　the　Weather　Research　and　Forecasting　and　Community　Multiscale　Air　Quality　(WRF-CMAQ)　models　and　a　＇zero-out＇　approach　to　investigate　contributions　of　air　pollution　transport　and　sources　to　aerosol　fine　particulate　matter　(PM2.5)　pollution　in　Chengdu　City　during　January,　April,　July,　and　October　2015.　The　results　showed　that　PM2.5　pollution　in　Chengdu　City　was　serious　during　these　months　and　reached　＞130　μg•m-3　in　January.　Highest　concentrations　were　measured　in　the　city　center.　PM2.5　pollution　in　Chengdu　and　the　surrounding　cities　was　found　to　exhibit　regional　characteristics.　Since　the　air　mass　was　stable　during　the　monitoring　periods,　the　interregional　transmission　capability　of　air　pollution　was　poor,　and　thus　local　sources　were　the　main　contributors　(61%　of　the　annual　average　concentration)　to　PM2.5　pollution　in　Chengdu　City.　The　contributions　of　local　sources　in　April　and　July　were　higher　than　of　those　in　January　and　October.　We　found　that　the　main　sources　of　PM2.5pollution　in　Chengdu　City　were　automobile　emission　(29%　of　the　total),　dust　(26%),　and　domestic　pollution　(24%),　and　should　be　further　controlled　in　the　future.　©　2020,　Science　Press.　All　right　reserved.