  In this paper, we construct two component dark matter model and revisit
fine-tuning, unitarity and vacuum stability problem in this framework. Through
Higgs-portal interactions, the additional scalar and vector singlet field can
interact with the SM particles. The parameter space of the model are severely
constraint by observed relic density and direct detection experiments. We found
that, unlike the SM, the fine-tuning problem is relaxed due to the modified
Veltman condition. The vacuum stability problem is addressed, the additional
contributions from two DM singlets to the $\beta$ function make the Higgs
quartic coupling $\lambda(\mu)$ be positive up to Planck scale in some
parameter space.
