To provide an outside particle circulating device for a circulating fluidized bed reducing device, improving a partial collecting efficiency and treating a material having a high ratio of fine powder.

A circulating fluidized bed reducing device, consisting of a fluidized bed reducing device and an outside particle circulating device 7, is provided with a bypass pipeline, extracting a part of process gas out of a descending pipe from a third cyclone 12 connected to a second cyclone 9 connected to a first cyclone 8 connected to the gas outlet port of a fluidized bed reducing furnace 1. In order to change the non-circulating third cyclone 12 into a down blow type cyclone, the bypass pipeline, extracting a part of process gas out of the lower part of the third cyclone 12, is provided with a fourth cyclone while the bypass pipeline is provided with a flow meter and a flow rate regulating meter to control the amount of extracted gas.