This　paper　is　devoted　to　studying　the　thermal　and　mechanical　properties　of　aminated　graphene　(AG)/epoxy　nanocomposites　connected　by　covalent　bond　using　molecular　dynamics　(MD)　simulation.　The　effects　of　crosslinking　degree,　mass　fraction　and　functionalized　graphene　(FG)　type　on　AG/epoxy　nanocomposites　are　considered.　The　elasticity　modulus　(E),　the　glass　transition　temperature　(T-g),　the　coefficient　of　thermal　expansion　(CTE)　and　the　interfacial　energy　(E-int)　are　also　investigated.　The　MD　simulation　results　indicate　that,　when　the　mass　fraction　of　AG　is　between　1.2%　and　3.1%　and　crosslinking　degree　reaches　about　70%,　the　E,　T-g,　E-int　and　CTE　of　AG/epoxy　nanocomposites　are　significantly　improved　compared　with　those　of　pure　epoxy　and　graphene/epoxy　nanocomposites.　The　reason　is　that　AG　not　only　possesses　some　excellent　thermodynamic　properties　of　graphene,　but　also　has　the　function　of　curing　agent　to　crosslink　with　epoxy　monomer　to　form　the　carbon-nitrogen　(C-N)　covalent　bond.　A　better　interfacial　interaction　between　nanoparticles　and　epoxy　is　essential　in　enhancing　the　thermal　and　mechanical　properties　of　nanocomposite　materials,　which　will　provide　a　microscopic　theoretical　basis　for　the　study　of　epoxy　nanocomposites.