A steering wheel mounted on a forklift 1 is provided with a steering wheel knob 17 which can be operated with one hand holding it. The steering wheel knob 17 has an approximately egg-like shape with switches 46, 47 provided on its end face. Incorporated in the steering wheel knob 17 are a transmission circuit 49, which radio-transmits a signal when the switches 46, 47 are operated, and a battery 51. The signal transmitted from the steering wheel knob 17 is received by a reception section 68 on a vehicle body 2 and a controller 48 executes predetermined control based on that signal.