A board-like division member is provided that extends in a vehicle body transverse direction so as to divide a portion of the engine room into an upper region and a lower region along in an engine room height direction. An engine is mounted downwardly of the division member. An exhaust treatment apparatus is mounted upwardly of the division member for treating exhaust gas from the engine. An air discharge portion is formed in a lateral face region of the hood which corresponds to a position of the division member in the engine room height direction. Air present inside the engine room is discharged to the outside through this air discharge portion.