  We study neutrino and dark matter based on a gauged $U(1)_R$ symmetry in a
framework of radiative seesaw scenario. Identifying dark matter as a bosoninc
particle, it interacts with quark and lepton sectors through vector-like
heavier quark and leptons, and plays an role in generating neutrino mass matrix
together with neutral heavier fermions. We explore several constraints for
masses and couplings related to dark matter by computing relic density and
direct search, taking the neutrino oscillation, lepton flavor violations, and
muon anomalous magnetic moment into account. Finally, we briefly mention
semileptonic decays and neutral meson mixings at one-loop box diagrams through
dark matter.
