To facilitate the wiring works of a curved part of an accelerator cable, to wire the same length accelerator cable irrelevant to a right-hand-drive vehicle or a left-hand-drive vehicle, and to reduce the cost by capable of using components in common.

This intake system structure is provided with a throttle lever 88 in one side in the left/right direction of the vehicle intersecting with an intake air flow direction of a throttle body 24, and the throttle lever is disposed in the center of an engine room 4 and rearward of an air cleaner 22. This structure is characterized in that the accelerator cable having one end side locked to the throttle lever 88 is directed to the front side of the vehicle, the accelerator cable 90 is curvedly wired on the air cleaner 22 disposed in the central part of the engine room so as to direct to the vehicle rear side, and a clamp retaining the curvedly wired accelerator cable 90 is provided on the air cleaner upper surface.