Natural　gas　hydrate　is　a　new　type　of　clean　energy　that　has　broad　application　prospects.　However,　the　change　of　temperature　and　pressure　conditions　in　the　process　of　hydrate　mining　will　cause　the　dissociation　of　hydrate,　which　lead　to　the　loss　of　cementation　strength　of　hydrate-bearing　sediments.　Meanwhile,　micro-cracks　and　defects　in　the　sediments　expand　gradually,　the　hydrates　between　the　soil　particles　are　damaged　and　broken　in　the　loading　process.　However,　in　the　previous　investigations　of　the　multi-field　coupling　model　on　hydrate　dissociation　process,　the　damage　evolution　process　of　sediment　structure　and　its　influence　on　the　coupling　process　are　ignored.　Therefore,　the　Weibull　distribution　of　three　parameters　and　residual　strength　correction　coefficient　are　introduced　into　the　damage　statistical　constitutive　model　in　this　paper　based　on　the　continuous　damage　theory,　and　the　damage　statistical　constitutive　model　of　hydrate-bearing　sediment　considering　the　influence　of　damage　threshold　and　residual　strength　is　established.　And　then,　the　constitutive　model　is　embedded　in　the　multi-field　coupling　model　of　the　hydrate　dissociation　process,　and　the　thermo-hydro-　mechanical-chemical　(THMC)　multi-field　coupled　mathematical　model　considering　damage　of　hydrate-bearing　sediments　is　proposed.　Finally,　based　on　the　model,　the　influence　of　sediment　structural　damage　on　the　deformation,　pressure　and　temperature　of　sediment　reservoirs　during　hydrate　dissociation　are　discussed.　It　can　be　shown　from　the　computational　results　that　the　structural　damage　of　hydrate-bearing　sediments　has　a　significant　effect　on　the　multi-field　coupling　process　about　the　dissociation　of　hydrates,　and　its　influence　increases　gradually　with　the　increase　of　dissociation　time.　©　2019,　Science　Press.　All　right　reserved.