Disgregating device for disgregating biological material, in particular for the preparation of cell suspensions or tissue micrografts or microfragments of tissue, comprising: - a hollow outer body, defining an inner chamber; - a perforated plate or disgregating grid, fixed, having a plurality of microholes provided with sharp edges, said disgregating grid being housed transversely in said inner chamber so as to define an upper loading chamber apt to be loaded with the biological material to be disgregated and a lower collecting chamber apt to collect the biological material, once disgregated (MB'); and - a bladed rotor, rotating in said inner chamber, said bladed rotor being apt to co-operate, rotating, with said disgregating grid, fixed, so as to feed and bring the biological material, contained in the upper loading chamber, into contact and to co-operate with the microholes, with sharp edges, of said disgregating grid, and therefore cause the disgregation of the biological material while it passes through said microholes; characterised in that the microholes of said perforated disgregating grid have dimensions or a diameter of between 70 and 80 μm, and more preferably have dimensions or a diameter of about 75 μm, in that the microholes of said disgregating grid are formed by means of a process of manufacturing by moulding of the die-punch (M, P) type, using a moulding punch of the polygonal-based pyramid-shaped type, in that said moulding punch and the corresponding die are configured in such a way that each of said microholes is obtained through breakage and tearing of the material of a metal sheet and has an irregular sharp edge, through the effect of this breakage or tearing, defining a plurality of sharp tips, and in that said outer body defines a through hole, substantially vertical, which extends between an upper edge of said outer body and the base of said collecting chamber, wherein said through hole has the function of allowing the extraction of the disgregated biological material (MB'), accumulated in said collecting chamber, whereby said disgregating device is apt to prepare cell suspensions and set up tissue micrografts that preserve intact the characteristics and cell viability of the original biological material, not disgregated, thereby avoiding the use of chemical reagents in the preparation of these cell suspensions and in the setting-up of these tissue micrografts. - a hollow outer body, defining an inner chamber; - a perforated plate or disgregating grid, fixed, having a plurality of microholes provided with sharp edges, said disgregating grid being housed transversely in said inner chamber so as to define an upper loading chamber apt to be loaded with the biological material to be disgregated and a lower collecting chamber apt to collect the biological material, once disgregated (MB'); and - a bladed rotor, rotating in said inner chamber, said bladed rotor being apt to co-operate, rotating, with said disgregating grid, fixed, so as to feed and bring the biological material, contained in the upper loading chamber, into contact and to co-operate with the microholes, with sharp edges, of said disgregating grid, and therefore cause the disgregation of the biological material while it passes through said microholes;