In　order　to　improve　the　characteristic　of　electromagnetic　interference　resistance　of　cement　based　material,　the　graphite-cement　based　composites　were　prepared.　The　resistivity,　electromagnetic　shielding　effectiveness　and　mechanical　performance　of　the　composites　were　measured.　The　results　indicate　that　the　resistivity　tends　to　decreasing　with　increasing　the　mass　fraction　(the　same　below)　of　graphite　to　a　certain　value.　The　decrease　of　resistivity　is　obvious　when　graphite　is　added　in　the　range　of　5%　to　10%,　and　when　the　graphite　content　exceeds　15%,　the　change　of　resistivity　is　slight.　The　electromagnetic　shielding　effectiveness　of　the　composites　increases　with　increasing　graphite　content　and　reaches　the　maximum　when　the　graphite　content　is　15%.　However,　the　flexural　strength　and　compressive　strength　decrease　with　increasing　graphite　content.