In　hygrothermal　environment,　water　is　easy　to　invade　the　epoxy　resin　aging,　resulting　in　a　decline　in　electrical　insulation　performance.　In　order　to　clarify　the　microcosmic　mechanism　of　epoxy　resin　wet　thermal　aging,　the　effects　of　temperature　and　water　content　on　the　crosslinking　system　of　epoxy　resin　were　studied　by　molecular　dynamics　simulation　technology.　The　results　show　that　after　water　invasion,　part　of　the　free　volume　is　occupied　first.　With　the　increase　of　moisture　absorption,　swelling　and　plasticization　of　the　material　occur,　which　causes　the　glass　transition　temperature　to　first　increase　and　then　decrease.　On　the　one　hand,　high　temperature　intensifies　the　molecular　movement,　increases　the　energy　of　the　system,　and　makes　the　system　unstable.　On　the　other　hand,　high　water　content　enhances　the　interaction　between　epoxy　resin　and　water　molecules,　and　the　combined　action　of　the　two　aggravates　the　damp-heat　aging　of　epoxy　resin.　©　Beijing　Paike　Culture　Commu.　Co.,　Ltd.　2025.