Abstract: A trailer wherein a body frame supports front and rear wheels rotatably at the left and right side portions thereof; a cargo base member has a plurality of rotors for transferring a cargo, arranged rotatably and in a mutually spaced manner on the cargo base member; and stoppers are provided at the front, rear, left and right portions of the body frame and the central portion of the cargo base member so that the stoppers can be vertically moved by operating rods connected to all of the stoppers for holding the cargo on the cargo base member. The front, rear, left and right stoppers are urged so that the stoppers normally project to a level higher than the upper surfaces of the rotors on the cargo base member. The central stopper is provided pivotably and movable vertically so that the cargo can be rotated easily on the cargo base member.