To provide a small-sized trailer for a farm work vehicle capable of attaining safe and efficient loading and unloading in a short time.

This trailer has a structure in which at least rear edges of a frame and a deck supported by a pair of right and left wheels and an axle of the wheels, and a joint bar are supported at a rear edge at rear side more than a front edge of the deck frame, and the deck is inclined with its support point as a fulcrum. When the deck is inclined or returned to be horizontal, the deck is smoothly operated by a damper of which the one end is jointed with the joint bar and the other end is jointed with the frame or the deck under movable condition so as not to be abruptly operated. Especially, for a farm work vehicle having a crawler, a crawler guide is provided at an inner side or an outer side of the crawler so that the vehicle body may not be shifted. Besides, at the time of loading/unloading the farm work vehicle, a tread board attached to the rear edge of the deck is used.