Abstract: This invention relates to a loading guide removably mountable on a boat trailer to maintain a centering and guiding force on the boat hull as it is moved on the guide rollers through a winch and cable system associated with the trailer. The loading guide employs a pair of crossed guide levers pivotally connected to the loading guide and having guide roller members at the ends of the same. The guide levers are pivotally interconnected at their point of crossing on the frame of the loading guide and the opposite ends are interconnected through links coupled to a tensioning spring which applies a force to the roller members on the ends of the crossed guide levers engaging the boat hull for centering the same. The guide levers, which are biased from the single spring, insure a positive centering force which increases as the hull is displaced from a centered position to insure positive centering of a boat on a trailer.