High-viscosity　asphalt　(HVA)　provides　excellent　cracking　and　rutting　resistance　for　ecological　permeable　pavement.　However,　HVA　suffers　from　severe　aging　due　to　higher　construction　temperatures　and　rich　porous　structures,　which　limited　its　applications　for　urban　sustainability.　Currently　there　is　still　a　lack　of　knowledge　about　the　thermal　aging　effects　and　mechanisms　of　HVA.　In　this　study,　the　effects　of　thermal　aging　on　the　morphological　structures,　rheological　and　fatigue　properties　of　two　HVAs　(i.e.　HVA-1　and　HVA-2)　at　five　aging　levels　via　Simple　Aging　Test　(SAT)　are　systematically　investigated.　HVA-1,　characterized　by　loosen　and　coarse　reticulated　structures,　undergoes　significant　structural　changes　during　aging,　whereas　HVA-2,　characterized　by　dense　and　fine　reticulated　structures,　experiences　fewer　alterations.　The　changes　in　the　modulus　master　curves　of　HVAs　become　more　gradual　after　aging,　indicating　the　reduced　temperature　sensitivity.　Multiple　stress　creep　recovery　results　reflect　that　two　types　of　HVAs　exhibit　totally　different　dominance　of　oxidation　or　polymer　degradation　depending　on　aging　level.　Liner　amplitude　sweep　(LAS)　results　based　on　damage　mechanics　analysis　reveal　that　aging　leads　to　an　increase　in　the　accumulated　strain　energy　observed　in　stress-strain　curves　for　both　HVAs.　As　aging　progresses,　the　proportion　of　elastic　energy　decreases　due　to　polymer　degradation,　resulting　in　a　reduction　in　fatigue　life.　Especially,　the　fatigue　life　of　aged　HVAs　significantly　decreases　after　SAT40.　LAS　results　based　on　fracture　mechanics　analysis　show　that　the　crack　length　increases　with　aging　due　to　polymer　degradation　and　asphalt　phase　hardening.　Aging　effect　on　crack　length　was　limited　at　initial　stage　but　becomes　more　significant　as　crack　extends.　As　aging　deepens,　the　crack　initial　stage　of　HVAs　tends　to　lengthen　while　the　crack　extension　stage　tends　to　shorten.　Moreover,　the　crack　growth　process　of　HVAs　follows　a　two-stage　behavior　of　crack　initiation　and　propagation　under　certain　aging　levels　from　the　relationship　between　energy　release　rate　and　crack　propagation　rate.　Overall,　the　thermal　aging　kinetics　of　various　HVAs　differ　significantly　in　the　structures,　rheological　and　fatigue　properties　as　aging　deepens.　HVA-2　with　loosen　and　coarse　structures　exhibits　greater　aging　resistance　and　lower　temperature　sensitivity　than　HVA-1　with　dense　and　fine　structures.　©　2023　Elsevier　Ltd