PURPOSE: To extend a grass gathering box downward by lowered portion of the upper face of a bonnet and increase capacity of the box by arranging a radiator taller than an engine in front of the engine, and forming the upper face of a bonnet into a rear down slope in side view.

CONSTITUTION: In a riding type mower, a mower 1 is elevatably arranged on the forward position of a vehicle body, a driving part 2 is provided on the front part of the body, an engine bonnet 4 in which an engine 3 is mounted is arranged on the rear part of the body, and a grass gathering box 5 to receive grass from the mower 1 is arranged on the position over the bonnet 4. In this case, a radiator 11 is standingly provided in front of the engine 3 and in rear of a seat 10, and a coolin fan 12 is provided in the rear of it. The grass gathering box 5 is supported with a supporting frame 15 standing from the rear end part of a frame 9, and the underside is formed into a rear down slope along the upper face of the engine bonnet 4.