Abstract: An improved process for producing superfines of metal is disclosed, which comprises reacting a metal halide containing gas with a reducing gas by causing to flow both the stream of a metal halide containing gas and the stream of a reducing gas concurrently but at different velocities so as to form an interfacial instability region in the reaction zone, and nuclei are formed in said instability region whereas said reaction zone is quenched (cooled) to inhibit the excessive growth of said nuclei. Application of a magnetic field to the reaction zone can enhance the degree of fineness and magnetic properties of the superfines thus produced.