Bi2DyFe5O12 garnet films were prepared by crystallization of sputtered amorphous films. The magnetic properties and influence of Bi were studied. The substitution of Bi results in the decrease of low-temperature magnetization and compensation temperature and increase of room-temperature magnetization and Curie temperature. This behaviour may be attributed to the influence of the Bi3+ ions on the superexchange interaction and to the spin polarization of Bi3+ ions. It was found that the bismuth enhances the effective magnetic moment of Dy3+ ions.