PROBLEM TO BE SOLVED: To dust a dust prevention net in a wide range by sending air to the dust prevention net even at the outer circumferential side of a dusting axial-flow fan.SOLUTION: In a combine 1, a cooling fan 13 of an engine 12 is provided so as to suck 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 when 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 dusting shroud 20 for blocking suction air wrapping around the upper stream side of the dusting axial-flow fan 19 from a space between the dusting axial-flow fan 19 and the dust prevention net 11c when the dusting axial-flow fan 19 is operated.
