  We study a two loop induced seesaw model with global $U(1)_{B-L}$ symmetry,
in which we consider two component dark matter particles. The dark matter
properties are investigated together with some phenomenological constraints
such as electroweak precision test, neutrino masses and mixing and lepton
flavor violation. In particular, the mixing angle between the Standard Model
like Higgs and an extra Higgs is extremely restricted by the direct detection
experiment of dark matter. We also discuss the contribution of Goldstone boson
to the effective number of neutrino species $\Delta N_{\rm eff}\approx0.39$
which has been reported by several experiments.
