Supporting device for at least one sliding door for closing at least one space, wherein said supporting device includes guiding means essentially parallel to the width extension of said space, said guiding means being intended to guide the sliding of at least one trolley supporting said door and wherein the sliding of said trolley occurs according to a sliding direction essentially parallel to the width extension of the body of said space and wherein said trolley includes a plate provided with wheels (15, 16, 17, 18) intended for sliding in a condition of coupling with said guiding means, said plate supporting a bracket intended to support said door, said bracket being mobile with respect to said plate according to a direction of extraction and/or insertion at least partially inclined with respect to said sliding direction, the movement of said bracket with respect to said plate being guided by means of coupling devices (25, 26, 27, 28) between at least two positions of which: - a first position is a closed position of said space in which said bracket is in an essentially retracted condition and in a condition of approach with respect to the body of said space with said door in a closed condition of said space; - a second position is a sliding position of said door in which said bracket is in an essentially extracted condition and in a condition of moving away with respect to the body of said space with said door placed essentially in front of said space and spaced with respect to said space by a distance; wherein said coupling devices (25, 26, 27, 28) guiding the movement of said bracket with respect to said plate include at least one slot (25, 26) and at least one pin (27, 28), in which said at least one slot (25, 26) constitutes a guiding profile within which the movement of said at least one pin (27, 28) is guided, said at least one slot (25, 26) being of an oblong shape with a longitudinal extension essentially parallel with respect to said direction of extraction and/or insertion, said at least one slot (25, 26) being obtained on said plate and said at least one pin (27, 28) being fastened to said bracket, said supporting device being characterised in that said coupling devices guiding the movement of said bracket with respect to said plate further include at least one circular plate (19, 20), said at least one circular plate (19, 20) being rotationally fastened to said plate at a corresponding hinging point (21, 22) and said bracket being fastened to and integral with said at least one circular plate (19, 20), and further characterised in that said at least one slot (25, 26) is shaped as an arc of a circle with the centre corresponding to said hinging point (21, 22) so that the rotation of said at least one circular plate (19, 20) causes the movement of said bracket with respect to said plate between said at least two positions, that is to say, said first position in which said bracket is in an essentially retracted condition and said second position in which said bracket is in an essentially extracted condition, said coupling devices guiding the movement of said bracket with respect to said plate including two of said circular plates (19, 20), a first circular plate being rotationally fastened to said plate at a corresponding first hinging point and a second circular plate being rotationally fastened to said plate at a corresponding second hinging point, said bracket being rotatably fastened on said circular plates (19, 20) in correspondence of said at least one pin (27, 28) made in the form of a bearing sliding in said at least one slot (25, 26), said at least two of said circular plates (19, 20) being connected to each other by means of a rod hinged on said circular plates (19, 20), said rod coordinating the rotation of the corresponding circular plates (19, 20) reciprocally restraining the rotation of the latter according to corresponding angles of rotation. - a first position is a closed position of said space in which said bracket is in an essentially retracted condition and in a condition of approach with respect to the body of said space with said door in a closed condition of said space; - a second position is a sliding position of said door in which said bracket is in an essentially extracted condition and in a condition of moving away with respect to the body of said space with said door placed essentially in front of said space and spaced with respect to said space by a distance;