  Cosmological implications of neutrinos are reviewed. The subjects considered
involve: (a) bounds on neutrino mass from the observational limits on the
universe age and the Hubble constant both in cosmology with and without
cosmological constant; (b) distortion of spectrum of cosmic neutrinos; (c)
bounds on neutrino mass from primordial nucleosynthesis; (d) lepton asymmetry
of the universe; (e) neutrino oscillations and possible new sterile neutrinos;
(f) neutrino role in large scale structure formation.
