Magnetic circular dichroism (MCD) in the YBa2CU3O7-x c-oriented epitax
ial optically transparent films has been investigated. For superconduc
ting (sc) and non-sc samples the MCD dependence on magnetic field is d
escribed well by the linear law up to 7 T. The dispersion of MCD is di
fferent in sc and non-sc films. The paramagnetic behavior of the tempe
rature dependence of amplitude is peculiar to most of the MCD bands.