Abstract: An automatic sewing device (1), particularly for hosiery knitting machines, characterized in that it comprises a supporting arm (2, 3, 4) for an oscillating means (7, 8), which comprises at least one first oscillating assembly (7), constituted by a semicircular ring, and at least one second oscillating assembly (8), constituted by a second semicircular ring, a means (11, 12) for actuating the oscillating assemblies which is suitable to produce at least one open position, in which the oscillating assemblies substantially form a ring which has the same size as the needle cylinder (24) from which it picks up a hosiery item at the end of the knitting process, and at least one closed position, in which the oscillating assemblies close the hosiery item in a semicircular arrangement, ready to be sewn, in a sewing station, the support being movable from at least one position for gripping the hosiery item from the needle cylinder to at least one position for applying the hosiery item to the sewing station.