The invention provides a method for recovering nonferrous metals, rare and noble metals and 
iron powder from 
steelmaking flue dust. The method comprises the following steps: mixing the 
steelmaking flue dust with a chlorination agent and a 
reducing agent, adding the obtained mixture to a tunnel furnace, and carrying out a two-stage reaction, wherein a primary stage reaction is a medium temperature chlorination reaction and allows nonferrous metals and precious metals to volatilize and enter 
flue gas, the 
flue gas is used as a 
nonferrous metal and 
precious metal extraction 
raw material after dusts are collected, and a 
secondary stage reaction is a high temperature reduction reaction and reduces iron into 
elemental iron which is discharged with 
kiln slag; and carrying out cooling, crushing and ball milling on the 
kiln slag to form a 
slag slurry with the 
granularity being smaller than 60 meshes, and carrying out 
magnetic separation to obtain the 
elemental iron powder and waste slag, wherein the 
iron content of the 
iron powder is greater than 86%, the 
iron powder can be used as commercial reduced iron 
powder, and the waste slag is sold to 
cement mills. The method allowing the chlorination and reduction 
metallurgy processes to be carried out in the tunnel furnace in a segmental manner has the advantages of process simplification, simplicity in operation, high 
thermal efficiency, low production cost and high comprehensive 
utilization rate, and is a new way for reasonable 
recovery of valuable metals in the 
steelmaking flue dust and high-efficiency 
resource utilization.