Device for facilitating the lowering of a landing gear by gravity, comprising at least on roller device (4) positioned on at least one closing panel (2) of the hatch for the landing gear in a contact area with the tire (1a) of the landing gear of an aircraft (7) on initiating its descent, the roller device (4) comprising a rigid roller device which can rotate freely about its axis (4a), and being positioned such that its axis is perpendicular to the path of the tire (1a) so that the tire will make the roller device (4) turn without sliding over it.