Marketed machine made completely in stainless steel. It is particularly suited for obtaining fillets of gilthead, bass and similar fish, including freshwater fish (trout); easily operated, it features a head-and-tail cutting method based on a wholly protected blade, positioned on the outside of the machine. Heads and tails of fish are cut by hand, it is then introduced through the upper conveying channel into the filleting section. This automatically allows to cut the fish lengthwise, with the ensuing expulsion of guts, fishbone and, separately, of the fillet.