PURPOSE: To obtain a photomagnetic recording film with an enhanced photomagnetic effect by incorporating a crystalline part having 10W500 grain diameter into the amorphous rare earth metal-transition metal alloy in an amorphous alloy film.

CONSTITUTION: A vessel 1 communicates with a vacuum evacuation system 5 and a gaseous Ar introducing system 6. An RF electric power source 7 for supplying high-frequency electric power between a substrate 3 and a target 4 and a DC electric power source 8 for impressing a negative bias voltage to the substrate 3 are connected in series between an anode and a cathode. An amorphous alloy film in the optical recording medium is formed by a high- frequency sputtering device. The amorphous alloy film is directly formed on a discoid and grooved acrylic substrate as the substrate 1 having 200mm diameter. Then a protective film of Si3N4, etc., is immediately formed on the formed amorphous alloy film while keeping the vacuum conditions. By such film formation, a photomagnetic recording medium contg. a crystallite part having 50W500 grain diameter in the amorphous structure of the amorphous alloy film is obtained. Besides, the alloy film consists of a rare earth metal-transition metal alloy.