PROBLEM TO BE SOLVED: To obtain smooth turning without derailing an autonomous traveling work vehicle when the autonomous traveling work vehicle is towed and moved by a manned traveling work vehicle.SOLUTION: A traction control device comprises: an autonomous traveling work vehicle 1 that comprises position calculation means for positioning a position of a machine body by using a satellite positioning system, and a control device 30 for causing a steering actuator 40 to travel by actuating the steering actuator 40 automatically so as to travel along a set travel path R a manned traveling work vehicle 100 on which an operator rides, and which comprises remote handling equipment 112 and can operate the autonomous traveling work vehicle 1 by the remote handling equipment 112 and a traction device 150 which connects the manned traveling work vehicle 100 and the autonomous traveling work vehicle 1. When the autonomous traveling work vehicle 1 is towed and moved by the manned traveling work vehicle 100, the control device 30 actuates the steering actuator 40 of the autonomous traveling work vehicle 1 so as to travel along a moving path M which is set in advance.
