PROBLEM TO BE SOLVED: To improve dusting effect of a dust prevention net by sending air to the dust prevention net even in the center of a dusting axial-flow fan.SOLUTION: In a combine 1, a cooling fan 13 of an engine 12 is provided so as to such the outside air through the dust prevention net 11c provided in an engine cover 11, the dusting axial-flow fan 19 capable of sending the air toward the dust prevention net 11c is provided between the dust prevention net 11c and the cooling fan 13, and the dusting axial-flow fan 19 is operated in such a state that the cooling fan 13 is stopped so as to blow off the dust attached to the outside of the dust prevention net 11c. The combine is equipped with a wind guide member 25 for guiding the air generated by the dusting axial-flow fan 19 at the downstream side of the dusting axial-flow fan 19 to the center of the dusting axial-flow fan 19.
