PURPOSE: To efficiently execute smelting reduction of metallic oxide, to improve the productivity and to enable drastic energy saving in a vertical furnace for executing the smelting reduction to the metallic oxide by forming packing layer of carbonaceous solid reducing agent into the furnace, executing blowing of reactive gas from upper and lower tuyeres at the lower part of a belly wall and injecting the powdery and granular metallic oxide from the upper step tuyeres.

CONSTITUTION: Plural thermometers 13 are arranged in the vertical direction on a furnace wall between upper stage tuyeres 2 and lower stage tuyeres 3 to measure temps. Based on these temp., a controller 15 adjust adjusting valves 10, 11 in the reactive gas piping at the upper and lower stage tuyeres 2, 3 thus to adjust the distribution of gas quantity supplied into the upper and lower stage tuyeres 3.