In　this　paper,　we　consider　the　large　time　behavior　of　the　Cauchy　problem　for　the　three-dimensional　isentropic　compressible　magnetohydrodynamic　(MHD)　equations.　The　global　existence　of　smooth　solutions　for　the　3D　compressible　MHD　equations　has　been　proved　by　Chen-Tan　[6],　under　the　condition　that　the　initial　data　are　close　to　the　constant　equilibrium　state　in　the　Sobolev　space　H-3.　However,　to　our　best　knowledge,　the　decay　estimate　of　the　highest-order　spatial　derivatives　of　the　solution　to　the　compressible　MHD　equations　has　not　been　solved.　The　main　goal　in　this　paper　is　to　give　a　positive　answer　to　this　problem.　Exactly,　under　the　assumption　that　the　initial　perturbation　is　small　in　H-l(R-3)　boolean　AND　(B)　over　dot(2,infinity)(-s)(R-3)　with　l　＞=　3,　s　is　an　element　of　inverted　right　perpendicular0,5/2inverted　left　perpendicular,　combining　the　spectral　analysis　on　the　semigroup　generated　by　the　linear　system　at　the　constant　state　and　the　energy　method　to　the　compressible　MHD　equations,　then　we　get　the　optimal　convergence　rates　of　any　order　spatial　derivatives　(including　the　highest-order　derivatives)　of　the　solution.　This　result　concern　with　the　optimal　time　decay　rates　of　the　solutions,　which　extends　the　work　obtained　by　Chen　[5]　for　the　compressible　Navier-Stokes　equations　in　R-3　to　the　3D　compressible　MHD　equations.　Moreover,　we　have　expanded　the　range　of　sfrom　(0,　3/2]　to　[0,　5/2],　compared　with　the　previous　results　on　optimal　decay　rates　of　global　strong　solutions　for　the　3D　isentropic　compressible　MHD　system.　(C)　2021　Elsevier　Inc.　All　rights　reserved.