Bonding　interface　quality　is　crucial　for　power　electronic　packaging,　while　the　alloyed　Ag　nanoparticle　sintered　joint　has　lower　crack　resistance　at　the　interface.　In　this　work,　a　sandwich　structure　nanoparticle　film　consisting　of　an　Ag　transition　layer,　nanoalloy　layer,　and　Ag　transition　layer　was　developed　for　interface-enhanced　lowtemperature　bonding.　The　optimized　sandwich　structure　increased　the　shear　strength　of　Ag-based　nanoalloy　sintered　joints,　reaching　5.6　times　for　Ag10Cu　and　2.0　times　for　Ag10Pd,　respectively.　The　low-temperature　spreadability　of　the　Ag　transition　layer　provided　a　micro-nano　structure　and　further　driving　force　for　nanoalloy　sintering　on　the　substrate.　Both　experimental　and　molecular　dynamics　simulation　results　revealed　that　these　nanoalloy　particles　spread　easier　and　realized　a　higher　effective　bonding　area.　This　interface-enhancing　strategy　enables　the　Ag-based　nanoalloy　a　high-reliability　die-attach　material　with　low-temperature　bondability.