  We propose a vector dark matter model from a hidden SU(2)_D gauge symmetry at
TeV scale. A scalar septuplet is introduced to break the SU(2)_D symmetry
spontaneously. The septuplet also play the role of a portal between the
standard model and the dark sector. We find that there are two different vacuum
configurations corresponding to the sign of the quartic coupling $\lambda_3$,
which yields different mass spectrum for the gauge bosons. For a $\lambda_3<0$,
the masses of gauge bosons are splitting, while for a $\lambda_3\geq0$, the
masses are degenerate. We also study the RG evolutions of the couplings, and
find that the perturbativity and vacuum stability can set a stringent bound on
the parameter space. For the phenomenological aspect, we consider the
experimental constraints including dark matter direct detection, indirect
detection, relic density, and Higgs couplings measurements. We find that there
are parameter space survive from all the constraints, and they can be tested in
future dark matter direct and indirect detection experiments.
