A retractable stopper device for a vehicle loading/unloading dock, said retractable stopper device comprising: - a frame attached or intended to be attached to the dock facing the loading/unloading location in front of the dock; - a movable stopper comprising a stopper body, with which the stopper is connected to the frame, and a stop face connected to the stopper body and against which a vehicle is intended to abut, the stopper being connected to the frame so as to be able to translate with respect to the frame between a deployed position, in which the stopper protrudes from the frame such that, in use, the stop face of the stopper protrudes forwards and above the dock so as to constitute a stop for the rear of a vehicle berthing the dock, and a retracted position, in which the stopper has been retracted towards the frame; - means for guiding the stopper between the retracted and deployed positions; and - means for controlling the movement of the stopper; the means for guiding the movable stopper comprising at least one guiding groove (4a, 4b) provided in either of the frame and the stopper body, and at least one rolling or sliding member (10a, 10b) mounted on or formed by at least one guiding shaft (9a; 9b; 12) integral with the other of the frame and the stopper body, the at least one rolling or sliding member (10a, 10b) being able to roll or slide within said at least one groove (4a, 4b) to guide the translation movement of the stopper body with respect to the frame, the stopper device being characterised in that the at least one guiding groove (4a, 4b) is provided along a direction inclined downwards and away from the stop face, and in that it further comprises impact absorbing means intended to absorb at least one part of the impact energy of a vehicle berthing the dock and abutting against the stop face, the absorbing means being disposed between the stop face and the stopper body. - a frame attached or intended to be attached to the dock facing the loading/unloading location in front of the dock; - a movable stopper comprising a stopper body, with which the stopper is connected to the frame, and a stop face connected to the stopper body and against which a vehicle is intended to abut, the stopper being connected to the frame so as to be able to translate with respect to the frame between a deployed position, in which the stopper protrudes from the frame such that, in use, the stop face of the stopper protrudes forwards and above the dock so as to constitute a stop for the rear of a vehicle berthing the dock, and a retracted position, in which the stopper has been retracted towards the frame; - means for guiding the stopper between the retracted and deployed positions; and - means for controlling the movement of the stopper; the means for guiding the movable stopper comprising at least one guiding groove (4a, 4b) provided in either of the frame and the stopper body, and at least one rolling or sliding member (10a, 10b) mounted on or formed by at least one guiding shaft (9a; 9b; 12) integral with the other of the frame and the stopper body, the at least one rolling or sliding member (10a, 10b) being able to roll or slide within said at least one groove (4a, 4b) to guide the translation movement of the stopper body with respect to the frame,