We investigate and discuss how surface corrugation affects the molecular rotational dependence of H-2 dissociative adsorption dynamics on Cu(100) by performing six-dimensional (6D) quantum dynamics calculations. We calculate the dissociative adsorption probability as a function of the initial rotational state J and the normal energy E-norm of incident molecules,and compare with the dissociative adsorption results obtained by four-dimensional (4D) quantum dynamics calculations where the surface is treated as flat. In our calculation, for the case of normal incidence, the increase in dissociative adsorption probability with increasing E-norm and the non-monotonic behavior of dissociative adsorption probability with respect to J are suppressed on a corrugated surface as compared to that on a flat surface.