Dispose　and　utilization　of　municipal　solid　waste　incinerator　bottom　ash　(MWSIBA)　is　one　of　the　imperative　issues　in　environmental　protection.　The　applicability　of　substitution　for　natural　aggregate　with　MWSIBA　in　asphalt　mixture　was　investigated　by　the　performance　and　micro　structure　of　asphalt　mixtures　with　diverse　porosity　levels　of　MWSIBA　(varying　the　replacement　percentage).　The　effects　of　porosity　of　MWSIBA　on　asphalt　mixture　performance　were　captured　by　determination　of　Marshall　stability,　tensile　strength,　dynamic　stability　and　the　maximum　flexural-tensile　strain.　The　horizontal　vibration　extraction　procedure　test　was　implemented　for　the　heavy　metal　leaching　concentration　to　evaluate　the　environmental　safety　of　MWSIBA　asphalt　mixture.　Chemical　and　micro-morphologic　characterization　for　MSWIBA　were　conducted　to　explore　the　mechanism　of　moisture　damage　resistance　of　asphalt　mixture.　Results　indicated　that　porosity　and　replacement　rate　of　MWSIBA　exerted　impacts　on　properties　of　asphalt　mixture.　The　rutting　resistance　of　asphalt　mixture　decreased　due　to　the　addition　of　MWSIBA,　resulting　in　a　reduction　in　high　temperature　performance.　MWSIBA　with　porosity　no　less　than　19%　was　beneficial　to　the　improvement　of　moisture　susceptibility　and　low　temperature　performance　of　asphalt　mixture,　while　high　mixing　amount　of　MWSIBA　was　unfavorable　to　the　properties　of　asphalt　mixture.　The　water　immersion　stimulated　the　hydration　reaction　in　MWSIBA,　leading　to　the　formation　of　C-(A)-S-H　gel　with　strong　cementation　property,　which　enhanced　the　adhesion　between　MWSIBA　and　asphalt　binder.　MWSIBA　asphalt　mixture　presented　lower　heavy　metal　concentration　and　better　environmental　safety　than　MSWIBA.　©　2022　Elsevier　Ltd