  Based on a localized crystal electric field model for the U^{4+} in the
(5f)^2-configuration, we analyze the resonant x-ray scattering spectra around U
M_{IV} and M_{V} edges in URu_{2}Si_{2}, taking full Coulomb and spin-orbit
interactions into account. We consider two level schemes, a singlet model of
Santini and Amoretti and a doublet model of Ohkawa and Shimizu, and assume the
antiferroquadrupolar order and the antiferromagnetic order as candidates for
the ambient pressure phase and the high pressure phase. It is found that the
spectral shapes as a function of photon energy are independent of the assumed
level scheme, but are quite different between the antiferroquadrupole and
antiferromagnetic phases, This may be useful to determine the character of the
ordered phase.
