The presence of a cosmic background of relic neutrinos is a robust prediction of the standard cosmological model. A direct detection is extremely difficult and still lacking. Nevertheless cosmological observations are a powerful probe of neutrino properties, and cosmological bounds on neutrino masses and number are in agreement with both theoretical predictions and laboratory searches. In this talk, I will review the basics of neutrino cosmology. I will then show current cosmological limits on neutrino properties, and discuss the prospects from next-generation surveys.