A cooling unit that is cooled by heat exchange with air is disposed at a rear side in a vehicle longitudinal direction of a power unit. Further, a cooling fan is disposed at a rear in the vehicle longitudinal direction of the cooling unit. Further, catalytic converters are disposed at a rear side in the vehicle longitudinal direction of the power unit. A periphery of these catalytic converters is surrounded by a heat insulator. A duct portion, that communicates an interior of the heat insulator and a space between the cooling unit and the cooling fan, is provided at this heat insulator.