Typical　climatic　environments　such　as　UV　radiation,　high　temperature　and　strong　wind　in　cold　and　arid　regions　have　a　significant　effect　on　asphalt　aging.　The　intent　of　this　work　is　to　reveal　the　evolution　law　of　natural　aging　of　SBS-modified　asphalt　under　the　complex　adverse　climate　environment　in　cold　and　arid　regions.　Furthermore,　the　contribution　rate　of　various　environmental　factors　of　natural　aging　of　asphalt　in　cold　and　arid　regions　was　analyzed.　Based　on　rheological　parameters,　this　paper　characterized　the　influence　of　natural　aging　on　the　viscoelastic　properties,　rutting　resistance　at　a　high　temperature,　fatigue　resistance　and　cracking　resistance　at　a　low　temperature　of　SBS-modified　asphalt.　The　evolution　law　of　natural　aging　performance　of　SBS-modified　asphalt　was　revealed.　A　quantitative　evaluation　index　(CIi)　of　natural　aging　contribution　rate　of　asphalt　was　put　forward　and　the　contribution　rate　of　various　environmental　factors　to　asphalt　natural　aging　was　analyzed.　The　results　showed　that　the　effects　of　simulated　aging　and　natural　aging　on　asphalt　properties　were　similar.　After　aging,　the　viscoelastic　properties　of　asphalt　were　deteriorated,　and　the　risk　of　fatigue　cracking　and　low　temperature　cracking　was　increased.　It　also　enhanced　the　deformation　resistance　of　asphalt　and　increased　the　rutting　resistance　at　high　temperature.　The　aging　contribution　index　CIi　obtained　based　on　rheological　parameters　such　as　complex　modulus　and　rutting　factor　could　directly　reflect　the　influence　of　different　natural　factors　on　the　performance　of　asphalt　during　aging.　Among　them,　the　effect　of　thermal　oxygen　was　more　obvious　on　the　natural　aging　of　SBS-modified　asphalt.