We study the impurity effect on the superconducting d-wave state accounting for the momentum-dependent impurity potential. We discuss the impurity-induced critical temperature suppression, local density of states in the vicinity of a single impurity, and the density of states in a superconductor with a spatial impurity distribution.

PACS numbers: 74.20.--z, 74.62.--c, 74.62.Dh, 74.72.--h