  We consider 2+1 flavor Wilson Chiral Perturbation Theory including the
lattice spacing contributions of O($a^{2}$). We adopt a power counting
appropriate for the unquenched lattice simulations carried out by the
CP-PACS/JLQCD collaboration and compute the pseudo scalar meson masses to one
loop. These expression are required to perform the chiral extrapolation of the
CP-PACS/JLQCD lattice data.
