  We find the condition that the primordial baryon asymmetry is not washed out
in the $SU(2)_{L}$ triplet Higgs model by solving the Boltzmann equation. We
further require that the model is compatible with the recent results of the
neutrino oscillation experiments and WMAP, and the constraints on the $\rho$
parameter imposed by the LEP. We finally obtain the allowed region of the
parameters in the model.
