To provide a method for effectively heating and reducing converter-sludge with convective heat-transfer on the packed bed by directly pre-treating into a carbon-contained formed body without performing oxidized curing.

The method for producing a reduced iron, with which the carbon-contained formed body formed into a pellet, briquette or extruded formed body after mixing and adjusting the humidity by adding carbonaceous material and binder into iron-oxide based dust kind and/or powdery ore, is heating-treated after drying, is characterized in that the carbon-contained formed body after drying is continuously supplied on a firing lattice having conveying function, and the packed bed having 10-100 cm layer thickness is formed on the firing lattice and the carbon-contained formed body is continuously heat treated at 1,000-1,350°C by making combustion-exhausted gas including no oxygen pass upward through the firing lattice and the packed bed from the lower part of the firing lattice while continuously shifting the packed bed with the conveying function of the firing lattice to make the reduced iron, and the reduced iron is continuously discharged from a discharging part arranged at end edge part of the down-stream side of the firing lattice.