  Dynamical Hall conductivity {\sigma}_H({\omega}) of a 2D electron gas with
impurities in the perpendicular magnetic field is analyzed. Plateau-like
behavior at low frequencies as well as at high frequencies provided the
complete filling of Landau levels is predicted. The broadening of a Landau
level separates two frequency regions with different behaviour. Imaginary part
of dynamical Hall conductivity reveals oscillations in the localized states
region. Comparison with the experiment is carried out.
