In allelic model X = ($x_1,;x_2,...x_{d}$), $M_f(t)$= f(p(t)) - ${{int}^{t}}_0$Lf(p(t))ds is a P-martingale for diffusion operator L under the certain conditions. In this note, we can show uniqueness of martingale problem associated with mean vector and obtain a complete description of ergodic property by using of the semigroup method.