A　significant　increase　in　effective　stress　can　be　induced　in　hydrate-bearing　reservoirs　when　the　depressurization　method　is　applied.　A　series　of　drained　triaxial　shear　tests　were　performed　on　hydrate-bearing　sediments　with　various　hydrate　saturations　to　investigate　their　mechanical　characteristics　under　effective　confining　pressures　of　up　to　20　MPa.　The　results　show　that　significant　particle　crushing　of　the　host　sand　occurs　during　shearing　under　high　pressures,　and　there　is　no　remarkable　effect　of　hydrate　saturation　on　the　degree　of　particle　breakage.　As　the　effective　confining　pressure　increases,　the　stress-strain　curves　of　the　hydrate-bearing　specimen　transformed　from　strain-softening　to　strain-hardening.　The　peak　stress　ratio　and　internal　friction　angle　of　the　sediments　gradually　decrease　and　tend　to　be　constant　with　the　increased　confining　stress,　whereas　the　cohesion　in　hydrate-bearing　sediments　exhibits　an　increasing　tendency.　The　critical　state　line　(CSL)　of　hydrate-bearing　sediments　in　the　e-　In　p＇　space　under　low-to-high　effective　confining　pressures　intersects　with　the　normal　consolidation　line　under　the　same　hydrate　saturation.　Furthermore,　the　CSL　moves　upward　and　rotates　clockwise　as　the　hydrate　saturation　increases.　(C)　2021　American　Society　of　Civil　Engineers.