To provide a fluidized bed reduction furnace, in which powdery and granular ore can uniformly and sufficiently be reduced and also, the making an equipment compact and the lowering of cost can be realized.

Plural stages of combination of fluidized bed spaces 11a, 12a, 13a containing a reverse conical tapered part at the lower part and no dispersion plate, and gas introducing holes 11b, 12b, 13b which blow reducing gas into the lower adjacent parts of these fluidized bed spaces from the outside, are arranged in the vertical direction in an integral furnace. An exhaust hole 15 of the reducing gas is arranged at the upper part of the uppermost stage in the fluidized bed space 11a. Gas supplying routes 21, 22, 23, in which the introducing quantity of gas can individually be controlled, are connected with each of the gas introducing holes 11b, 12b, 13b and each of the cross sectional areas A1, A2, A3 of the fluidized bed spaces 11a, 12a, 13a is made equal to the gas flow speed in each space.