  Hidden sector dark matter (DM) models with local dark gauge symmetry make a
natural playground for the $\gamma$-ray excess from the galactic center (GC).
In this paper, we first discuss in detail the GC $\gamma$-ray excess in scalar
dark matter model with local $Z_{3}$ symmetry which was recently proposed by
the present authors. Within this model, scalar DM with mass $30-70$GeV is
allowed due to newly-opened (semi-)annihilation channels of DM pair into dark
Higgs $\phi$ and/or dark photon $Z^{'}$ pair, and can fit the $\gamma$-ray
spectrum from the GC. Then we argue that the GC gamma ray excess can be easily
accommodated in hidden sector dark matter models where DM is stabilized by
local gauge symmetries, due to the presence of dark Higgs (and also dark photon
for Abelian dark gauge symmetry). As by-products, the Higgs portal interaction
between the dark Higgs and the SM Higgs boson can improve the EW vacuum
stability up to Planck scale, and enable the Higgs inflation scenario to have
potentially large tensor-to-scalar ratio, $r\sim O(0.01 - 0.1)$.
