In a small vehicle (1) provided with a power unit (5) including an internal combustion engine 2 and a power transmission system (3) and swingably attached to a body frame (4) below a seat (6), the wiring configuration for the throttle body in the small vehicle (1) includes a throttle body (52) disposed between the power unit and seat, an opening sensor (68) for detecting the degree of throttle opening, provided at an end of a throttle valve shaft (64) aligned along the width direction of the vehicle, an actuator (70) for controlling the throttle body, attached to the throttle body in the vicinity of the opening sensor, and a first wiring coupler (80) of the opening sensor and a second wiring coupler (81) of the actuator, the first and second wiring couplers (80, 81) being separately attached in the same front/rear direction so as to intersect with respect to the throttle valve shaft.