A method for drying a wet raw material such as a coal to be charged into a coke furnace in a fluidized bed dryer (3), through forming a fluidized bed (8) on a gas dispersing plate (5) positioning above wind boxes (4a, 4b), wherein the wet raw material having fallen into the wind boxes (4a, 4b) is recovered, and then, is transported to a charging chute (7) or the like via a second by-pass pipe (11), to thereby again charge it into the fluidized bed (8). The above method allows the drying of a wet law material having fallen into the wind boxes (4a, 4b) of the fluidized bed dryer (3) with reliability, which results in the achievement of a target water content of a treated material with reliability.