Natural　gas　hydrate　is　a　strategic　alternative　energy　source　which　are　widely　founded　in　seabed　sediments.　The　study　of　the　mechanical　properties　of　hydrate-bearing　sediments　is　the　key　content　to　ensure　the　safe　exploitation　of　gas　hydrate.　Hydrate　occurring　mechanisms　and　saturation　are　important　factors　affecting　the　mechanical　properties　of　hydrate-bearing　sediments.　In　this　work,　simplified　discrete　element　models　that　consider　the　hydrate　occurring　mechanism,　hydrate　saturation　and　confining　pressure,　were　generated　based　on　PFC　code.　Three　main　hydrate　occurring　mechanisms　including　pore　filling,　load　bearing　and　cementation　were　charac-terized.　The　triaxial　compression　simulation　was　then　conducted　to　investigate　the　model　mechanical　properties.　The　results　show　that　the　hydrate　of　cementation　mode　has　the　most　obvious　strength-enhancing　effect　on　sediments,　followed　by　the　load　bearing　model　and　pore　filling　model.　Hydrate　occurring　mechanism　also　affect　the　increasing　trend　of　sediment　strength　and　deformation　modulus　with　hydrate　saturation　and　confining　pressure.　The　influence　of　hydrate　occurrence　mechanism　on　the　mechanical　behavior　of　sediment　is　largely　controlled　by　the　interaction　between　hydrate　and　sand　particles　interface.　The　hydrate　of　cementation　mode　increases　the　cohesion　of　the　sediment　particles,　the　hydrate　of　pore　filling　mode　increases　the　friction　between　particles,　and　the　hydrate　of　load　bearing　mode　has　the　combined　effects　of　the　above　two.