In　this　paper,　uniaxial　compressive　strength　(UCS)　test　and　three-point　bending　(TPB)　test,　together　with　an　acoustic　emission　(AE)　system,　were　performed　to　investigate　the　mechanical　properties　and　AE　characteristic　changes　of　concrete　with　different　graphite　powder　(GP)　content.　The　results　show　that:　(1)　Poor　adhesion　and　low　interlocking　of　graphite　with　cement　stone　increase　the　initial　defects　of　concrete,　reducing　its　elastic　modulus　and　the　cyclo-hoop　effect,　and　thus　weakening　the　compressive　strength.　(2)　For　concrete　with　a　low　graphite　content,　the　second　sharp　rise　in　ringing　counts　or　energy　released　during　the　compressive　process　can　be　regarded　as　a　failure　alarm.　However,　as　GP　content　increases,　the　second　sharp　rise　fades　away,　while　the　first　sharp　rise　becomes　more　visible.　At　high　GP　content,　the　first　sharp　rise　is　better　for　predicting　failure.　(3)　The　initial　defects　caused　by　GP　significantly　lower　the　initial　fracture　toughness,　but　its　bridging　effect　greatly　increases　the　critical　crack　mouth　opening　displacement　and　thus　significantly　enhances　the　unstable　fracture　toughness　of　concrete,　by　up　to　9.9%　at　9%　GP　content.　(4)　In　contrast　to　compressive　process,　the　sharp　increase　in　AE　signals　preceding　failure　during　the　fracture　process　cannot　be　used　to　predict　failure　because　it　occurs　too　close　to　the　ultimate　load.　However,　as　GP　can　significantly　increase　the　AE　signals　and　damage　value　in　the　stable　period,　such　failure　precursor　information　can　provide　a　safety　warning　for　damage　development.