A combination of a wall lower guide device for a sliding door and of a door moving along said guide, the door comprising a body having an inner first surface or face movable frontally to a wall to which the guide is associated, opposing lateral faces connecting said first surface to an outer second surface or face of the door, an upper side, and a lower side which is movable over a plane or floor from which said wall rises and over which the door slides, a guide element of the wall lower guide device being positioned in proximity to said plane and along said wall to guide the movement of said door along said wall, in this latter there being provided an aperture to be closed by said door, said wall lower guide device comprising a connection member, said connection member comprising a L-shaped body presenting a first free end and a second free end, said ends (23, 24) being fixed to corresponding first and second pins (15, 26), the first pin being respectively movable slidingly and rotatingly within the guide element and the second pin being hinged to the door, said connection member guiding the door directly along the guide element and parallel to itself towards the wall when the door is in a position corresponding with said aperture such as to close it, elastic return means (45, 46) being provided to facilitate detachment of the door from the wall and to maintain it detached therefrom, said elastic return means (45, 46) being associated with said connection member, said elastic return means being at least one spiral spring, preferably two spiral springs (45, 46), disposed about said second pin, for the second pin a support associated with the door being provided, said support presenting a portion adjustably fixed to one of the lateral faces of the door, the body of said connection member comprising a first and a second portion (22A, 22B) connected together, the first portion having the second end of the connection member carrying the second pin, the second portion having the first end of the connection member carrying the first pin, the first portion being close to the door, the second portion being close to the wall, said first and second portions (22A, 22B) being connected together in an adjustable manner, the inner first surface or face of the door supporting a seal element or gasket arranged to sealedly close the aperture when the door is closed thereonto, each elastic return means (45, 46) having a first end resting against the support for said second pin and a second end positioned along the second end of the body of said connection member, at least one and preferably two projections (30, 31) jutting from the portion of the support and adapted to support the second pin being provided, said projections presenting coaxial holes (33, 34) to receive corresponding ends (26A, 26B) of the second pin, said ends being axially locked in these holes (33, 34), said first and second portions (22A, 22B) of the connection member body being coupled together by screws and corresponding nuts or a corresponding plate with threaded holes, said screws being inserted through elongated holes or slots provided in one of said first and second portions (22A, 22B), said screws being inserted into corresponding holes of the other of said portions, said engagement enabling said portions (22A, 22B) to undergo relative movement and enabling the distance of the first portion from the wall, and hence of the door from this latter, to be varied.