Neutrinos in Cosmology

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.