PURPOSE: To efficiently and finely pulverize sponge iron to be a stable apparent density by supplying the sponge iron into a pulverizer, finely pulverizing, screening and adjusting a supplying quantity of sponge iron so that load current value in the pulverizer comes to the prescribed value.

CONSTITUTION: The sponge iron from a fresh raw material hopper 1 is supplied into Novorotor mill 4 for pulverizer through screw feeder 2 driven with a variable velocity motor 15 and belt bucket conveyor 3 and finely pulverized. This fine pulverized powder is supplied to a screen 10 through a blowing-up tube 7 and cyclone 8 and screened. The powder of plus sieve is again returned back to the above mill 4 and the powder of minus sieve is recovered into a hopper 11. In the above circulating type sponge iron pulverizing method, before-hand relation between the apparent density of minus sieve and load current values of motors 4, 5 for pulverizer 4, is obtained. Further, the above motor 15 is controlled through a converter 16 to adjust supplying quantity of the sponge iron, so that the detected load current value in the pulverizer 4 becomes the prescribed value corresponding to the target apparent density of minus sieve with an ammeter 14 used as a load setter in common.