To easily remove a main frame having a bad influence on departure angle or fuel consumption in non-traction in a coupler having a predetermined strength required for pulling a trailer.

This coupler for vehicle traction comprises a fixing tool 1 mounted to the back part of the bottom of a car body and a bar-like main frame 2 detachably attached to the fixing tool 1. The fixing tool 1 comprises a pair of right and left brackets 1A and 1B for supporting both ends of the main frame 2, and both brackets 1A and 1B are provided with an oscillatable latch 6 for holding both ends of the main frame 2 in cooperation with the brackets. The brackets 1A and 1B are provided with a screw member 11 for inhibiting oscillation of the latches 6, and the central part of the main frame 2 is provided with connecting metal 3 for connecting pulled vehicle. Thus, oscillation regulation of the latches 6 by the screw members 11 is released to oscillate the latches 6, thereby easily removing the main frame 2 from the brackets 1A and 1B. Therefore, when the pulled vehicle is not pulled, the main frame 2 is removed to recover the fuel consumption and the running performance of the vehicle.