To obtain the vehicle body-steering device of a paddy field working vehicle, wherein a rear wheel on the inside of turn is switched into a stopping state to enable the small turn of the working vehicle, when the front wheel is steered, and wherein the rear wheel can be switched in a simple structure.

When front wheels 1a, 1b are steered, a steering wheel side swinging link 23 connected to a pitman arm through a steering wheel side swinging rod 22 is swung, and the contact portions 23a, 23b of the steering wheel side swinging link 23 are brought into contact with a rear wheel side swinging link 24, and transmits the steering force. Thereby, the rear wheel side swinging link 24 is swung. Then, the operation portion 66a of a left rear wheel-switching device CBL connected to the rear wheel side swinging link 24 through a left rear wheel side interlock rod 21a, and the operation portion 66b of a right rear wheel-switching device CBR connected to the rear wheel side swinging link 24 through a right rear wheel side interlock rod 21b are swung. Thereby, the rear wheels 2a or 2b on the outside of the turn are driven, and the rear wheels 2a or 2b on the inside of the turn are stopped.