Finite　element　simulation　was　carried　out　for　analyzing　the　accumulative　rate　of　equivalent　strain　and　final　equivalent　strain　of　5052　aluminum　alloy　processed　by　constrained　groove　pressing　(CGP)　and　unconstrained　groove　pressing　(UGP).　In　addition,　experiments　were　conducted　for　investigation　of　grain　refinement　as　a　function　of　accumulative　rate　of　equivalent　strain　as　well　as　final　equivalent　strain.　The　results　show　that　CGP　has　a　higher　accumulative　rate　of　equivalent　strain　and　final　equivalent　strain　than　UGP.　Compared　with　UGP,　CGP　is　more　beneficial　to　grain　refinement　due　to　the　higher　accumulative　rate　of　equivalent　strain　and　final　equivalent　strain,　which　is　determined　by　two　different　mold　constructions　and　independent　of　the　material　and　processed　condition.　©　Copy　Right.