A boring and facing head, rotatively driven by the mandrel of a machine tool, with a turning tool mounted on a mounting slide, which may be controllably driven transversely of the axis (X) of the head body by a threaded shaft (12) operatively connected to a cylinder body (11), integral with a mandrel (4) and rotatably housing a ring gear (17), operatively connected to a gear wheel (19), driven by a controllable motor (8) and wherein the ring gear (17) comprises a circumferential tooth arrangement engaging with a gear wheel (52), integral with the driving shaft (12).