Thin films of ferrites, of the order of 1000 A thickness, have been prepared by vacuum evaporation of themetals, and subsequent high-temperature oxidation. Films of iron, nickel, cobalt, magnesium, and copperferrites, mixed ferrites, and mixed ferrite-aluminates, as well as yttrium iron garnet, have been prepared.X-ray powder diffractometry indicates that the ferrite films are single-phase spinels, while the garnet showsthe garnet structure. In many respects, the properties of the films are the same as those of bulk ferrites ofsimilar composition. The resistivity of the films can be controlled by proper oxidizing procedures. X-bandmagnetic resonance measurements indicate that the saturation magnetizations of the films are comparableto those of the corresponding bulk ferrites, though the films show larger resonance linewidths. It has beenpossible to prepare magnesium ferrite films with magnetizations from 2200 gauss to less than 500 gauss byproper annealing and quenching. The possible advantages of thin films are that they allow optical studiesof the material by transmission, and should permit determination of magnetic exchange constants throughobservation of spin wave resonances.