The　objective　of　this　study　is　to　investigate　the　intermolecular　interactions　between　polymers　and　asphalt　components　due　to　the　oxidation　of　reactive　oxygen　species　(ROS).　Quantum　chemistry　(QC)　and　molecular　dynamics　(MD)　were　employed　to　simulate　the　molecular　properties　and　intermolecular　interactions　between　SBS　and　asphalt　components　during　ROS　aging.　Multifield　optical　microscopy　was　utilized　to　analyze　the　microstructural　characteristics　and　validate　intermolecular　interactions　of　SBS　and　asphalt　components　during　ROS　aging.　The　results　show　that　asphaltenes　have　the　most　uneven　electrostatic　potential　(ESP)　distribution,　followed　by　resins　and　aromatics,　while　saturates　exhibit　the　most　uniform　ESP　distribution.　ROS　aging　leads　to　a　more　uneven　ESP　distribution　and　a　higher　polarity　for　HiMA　molecules,　especially　for　asphaltenes　and　resins　with　increased　formation　of　polar　functional　groups.　SBS　and　saturates　exhibit　small　energy　gaps　and　electronic　softness,　indicating　good　resistance　to　ROS　oxidation,　whereas　asphaltenes　and　resins　are　prone　to　free　radical　oxidation　reactions　with　ROS.　The　potential　ROS　oxidation　site　of　asphaltenes　and　resins　are　mainly　distributed　in　benzene　ring　regions　and　heteroatoms,　while　that　of　SBS　are　primarily　located　at　the　polybutadiene　chains.　The　interactions　between　SBS　and　asphalt　components　are　primarily　driven　by　van　der　Waals　forces.　However,　the　hydrogen　bonding　appears　after　ROS　aging,　enhancing　the　intermolecular　interactions.　The　interaction　energies　of　SBS-asphaltenes　and　SBS-resins　are　significantly　enhanced,　and　the　intermolecular　distances　are　shortened　as　ROS　aging　progresses.　Multifield　microscopy　observation　reveals　that　the　development　of　bee　structures　in　polymer　regions　is　significantly　faster　than　that　in　asphalt　regions,　indicating　a　significantly　enhanced　adsorption　of　asphaltenes　by　polymers　after　ROS　aging.　This　is　attributed　to　the　uneven　charge　distribution,　increased　polarity,　and　enhanced　reactivity　of　asphaltenes　and　SBS　due　to　ROS　aging.　This　study　contributes　to　a　molecular-atomic-level　understanding　of　the　intermolecular　interactions　between　polymers　and　asphalt　components　during　ROS　aging.　©　2024　Elsevier　B.V.