PURPOSE: To produce metal powder in which the content of oxygen is reduced by heating the metal of Ta or Nb to a specified temp. in the presence of oxygen activating metal.

CONSTITUTION: Metal powder (having about <1000 oxygen content) selected from the groups of Ta, Nb, Ta alloys and Nb alloys is charged to the inside of a vacuum vessel together with metal (such as Mg) having high oxygen affinity. Next, this vessel is heated to a temp. of about ≤0.7TM, oxygen is diffused from this metal powder, and the heating is continued for a time sufficient for producing the metal powder contg. about <300ppm oxygen. Furthermore, TM denotes the in-phase temp. of the metal, and the 0.7TM of Ta powder is about 2018°C and the 0.7TM of Nb powder is about 1650°C. In this way, the powder of Ta, Nb, Ta alloys or Nb alloys having <300ppm oxygen content can be obtd.