A unified theory of including all kinds of dark matters into a single species (field) is discussed. In particular, it is considered that the Warm Dark matter (WDM), the existence of which may be required by the detailed N -body simulations of galaxies using the ΛCDM model, is the right-handed neutrino, the Hot Dark Matter (HDM) is the lefthanded neutrino, and the Cold Dark Matter (CDM) is the first KaluzaKlein (KK) mode of neutrino. The study on how to detect the first KK neutrino mode as CDM by LHC, SuperK, and IceCube is also explained. Not only these detectors but also the recent experiments, such as DAMA/LIBRA, PAMELA, XENON100, and XMASS as well as the various satellite detectors including Planck should be examined.