Dynamic　compressive　tests　of　sand　under　passive　confining　pressure　were　carried　out　using　a　Split　Hopkinson　Pressure　Bar　(SHPB)　setup.　The　dynamic　response,　energy　dissipation　and　particle-breaking　behaviors　of　sand　subjected　to　high-speed　impact　were　investigated.　Sand　specimens　with　moisture　contents　of　0%,　2%,　4%,　8%,　10%　and　12%　and　relative　densities　of　0.1,　0.5　and　0.9　were　prepared.　The　variation　in　the　strain　rate　was　controlled　between　90　s(-1)　and　500　s(-1).　The　specimens　were　confined　in　a　designed　sleeve　to　create　passive　confining　pressure.　The　experimental　results　show　that　the　sand　specimens　were　extremely　sensitive　to　the　strain　rate.　When　the　strain　rate　was　less　than　400　s(-1),　the　stress　and　strain　of　the　specimens　increased　with　the　increase　in　the　strain　rate　but　decreased　when　the　strain　rate　exceeded　400　s(-1).　The　peak　strain　and　peak　stress　increased　with　the　increase　in　the　relative　density.　Particle　breakage　was　aggravated　with　the　strain-rate　increase.　Compared　with　the　specimen　without　water,　the　relative　breakage　rate　of　the　specimen　with　a　moisture　content　of　12%　decreased　by　30.53%　when　the　strain　rate　was　about　95　s(-1)　and　by　25.44%　when　the　strain　rate　was　about　460　s(-1).　The　analysis　of　energy　dissipation　revealed　the　essential　cause　of　sand　destruction.　The　specific　energy　absorption　rate　increased　with　the　increases　in　the　initial　relative　density　and　moisture　content.