  Estimations of magnetic fields of neutron stars, observed as radio and X-ray
pulsars, are discussed. It is shown, that theoretical and observational values
for different types of radiopulsars are in good correspondence. Magnetic fields
of X-ray pulsars are estimated from the cyclotron line energy. In the case of
Her X-1 this estimation exceeds considerably the value of its magnetic field
obtained from long term observational data related to the beam structure
evolution. Another interpretation of the cyclotron feature, based on the
relativistic dipole radiation mechanism, could remove this discrepancy.
Observational data about soft gamma repeators and their interpretation as
magnetars are analyzed.
