The present invention concerns an elevator cabin door folding around a vertical axis during its closing movement and is based on the concept of making the door subject to a continuous tension exercised by a energy accumulator (preferably a spring) in order to keep the door opened, while, on the other door side, a traction action in opposite direction is exercised by means of two traction means (6, 7) that always pull the door and that wind around a second motorised vertical axis (8). The cabin door can then be mechanically coupled with a landing entrance door (11) so that the cabin door opening provokes the landing entrance door opening by means of dragging. The necessary torque on the different vertical axes of the construction are preferably exercised by cylindrical or helicoidal coil spring acting directly on the axes. The invention advantage mainly consists in the construction simplicity coupled with the reduced overall dimension and with the possibility of forming pre-assembled cabin doors and landing entrance doors and thus ready to be installed on the spot.