Grain　of　H62　brass　was　refined　by　using　parallel　groove　pressing　and　cross　groove　pressing.　The　microstructure　of　the　specimens　after　groove　pressing　were　observed　by　optical　microscopy,　scanning　electron　microscopy　and　transmission　electron　microscopy.　The　results　show　that　sub-micron　and　nano-sized　deformation　twins　form　in　the　deformed　samples.　Compared　with　parallel　groove　pressed　samples,　grain　size　of　specimens　deformed　by　cross　groove　pressing　is　smaller,　and　there　are　higher　density　and　better　homogeneity　of　sub-micron　and　nano-sized　deformation　twins.　Hardness　of　cross-section　and　surface　of　the　deformed　samples　were　studied.　The　results　show　that　microstructure　of　the　specimen　deformed　by　cross　groove　pressing　is　much　more　homogeneous　and　its　hardness　is　much　higher　than　that　of　the　specimen　deformed　by　parallel　groove　pressing.