PURPOSE: To prevent temp. rise of a sliding gate and the loss of magnetic flux by inserting a magnetic shading plate capable of being cooled between a molten metal discharging runner provided with an induction heating coil and the sliding gate in a nozzle part.

CONSTITUTION: The molten metal 8 is caused to flow down from the molten metal discharging runner 2 connecting with lower part in a molten metal holding vessel 1 and supplied into an atomizing means 4 through the ceramic-made sliding gate 22 in the nozzle part. Inert gas is injected to the molten metal stream from atomizing nozzles 42 in this atomizing chamber 41 to form metal powder 9. In the above metal powder manufacturing apparatus, the large diameter and the small diameter induction heating coils 5, 6 are arranged around the above vessel 1 and the molten metal discharging runner 2, respectively to hold fluidity of the molten metal 8. Then, the magnetic shading plate 7 including electric conductive and non-magnetic cooling means as built-in, is inserted between the heating coil 6 and the sliding gate 22. By this method, the temp. rise of the sliding gate 22 and the loss of the magnetic flux are prevented. Further, it is desirable to make vacuum in the vessel 1 and prevent oxidization of the molten metal8.