The　strengthening　effect　of　graphene　blocking　dislocation　propagation　in　graphene　reinforced　copper　matrix　composites　(Gr-CMCs)　was　investigated　via　molecular　dynamics　(MD)　simulations.　Atomic　models　of　Gr-CMCs　including　an　edge　dislocation　(b　=　1/6　(1　1　2))　were　built　to　explore　dislocations　motion　and　structure　evolution　under　shear　deformation.　The　effects　of　the　rotation　angle　and　the　arrangement　of　graphene　were　taken　into　account.　The　interaction　between　the　graphene　and　an　edge　dislocation,　as　well　as　the　graphene　effect　on　the　dislocation　motion,　was　investigated.　The　results　indicate　that　the　graphene　has　a　significant　effect　on　the　motion　and　velocity　of　the　dislocation.　The　dislocation　velocity　decreases　significantly　when　it　reaches　the　graphene,　proving　a　good　blocking　effect　from　the　latter.　In　addition　to　the　blocking　mechanism,　the　new　dislocation　planes　that　form　near　the　graphene　when　the　rotation　angle　is　greater　than　45°　also　contribute　to　the　strengthening　of　the　Gr-CMCs.　Furthermore,　the　influence　of　the　distance　between　two　abreast　graphene　sheets　on　the　dislocation　motion　is　discussed.　It　is　found　that　the　strengthening　effect　can　be　improved　by　adjusting　the　angle　and　arrangement　of　the　graphene　in　order　to　decrease　the　dislocation　velocity　and　increase　the　dislocation　density.　The　results　of　these　simulations　may　provide　guidance　for　the　design　of　future　composite　materials.　©　2020　Elsevier　B.V.