Leveling device suitable for being used by a user for laying on a plane and leveling at least two adjacent tiles, said leveling device comprising a support suitable for being constrained below the tiles, and a pressing body placed over the tiles and suitable for being movably fastened to the support and for abutting and pressing with an abutting surface on at least one of the at least two tiles; said support comprising a base, suitable for being arranged under the at least two adjacent tiles, and a threaded pin which extends orthogonally to the base and having a thread; the pressing body comprising a cylindrical element having a longitudinal central axis and an external side surface which the user can grip and comprising internally a first jaw element and a second jaw element; the threaded pin being disposed between the first jaw element and the second jaw element when the support and the pressing body are coupled to each other; a first thread being obtained in the first jaw element and/or a second thread being obtained in the second jaw element; the first jaw element and the second jaw element being adapted to be alternately disposed according to a first configuration in which the first and second jaw elements (36, 38) are separated from each other, and according to a second configuration in which the first and second jaw elements (36, 38) are adjacent to each other, so that the first thread and the second thread form together a continuous thread which is homologous to the thread of the threaded pin; the first jaw element and the second jaw element being arranged at rest according to the first configuration; first coupling means (26, 74, 76, 78) being comprised to bring the first jaw element and the second jaw element from the first configuration to the second configuration, and viceversa; characterized in that the first coupling means include a covering disk in which a complex opening is formed centrally, the perimetric edge of which is defined by a first arched edge and a second arched edge which are arranged symmetrically with respect to the center of the complex opening, the distances between points of the perimetric edge being symmetrically opposed with respect to the center of the complex opening increasing homogeneously from a minimum length to a maximum length, equal respectively to the measure of the chord D1 which ideally connects the nearest ends between the first arched edge and the second arched edge, and to the measure of the chord D2, perpendicular to the chord D1, which chord D2 ideally connects the farthest ends between the first arched edge and the second arched edge; in that the covering disk being rotatable with respect to the cylindrical element; in that the first jaw element and the second jaw element being adapted to be disposed passing through the complex opening; and in that the perimetric edge is formed, in consecutive order, by the first arched edge, a first rectilinear edge, the second arched edge and a second rectilinear edge, in which the first rectilinear edge and the second rectilinear edge lie on a same straight line passing through the center of the complex opening. characterized in that the first coupling means include a covering disk in which a complex opening is formed centrally, the perimetric edge of which is defined by a first arched edge and a second arched edge which are arranged symmetrically with respect to the center of the complex opening, the distances between points of the perimetric edge being symmetrically opposed with respect to the center of the complex opening increasing homogeneously from a minimum length to a maximum length, equal respectively to the measure of the chord D1 which ideally connects the nearest ends between the first arched edge and the second arched edge, and to the measure of the chord D2, perpendicular to the chord D1, which chord D2 ideally connects the farthest ends between the first arched edge and the second arched edge; in that the covering disk being rotatable with respect to the cylindrical element; in that the first jaw element and the second jaw element being adapted to be disposed passing through the complex opening; and in that the perimetric edge is formed, in consecutive order, by the first arched edge, a first rectilinear edge, the second arched edge and a second rectilinear edge, in which the first rectilinear edge and the second rectilinear edge lie on a same straight line passing through the center of the complex opening.