A machine tool equipped with a supporting body and at least one tool-holder spindle, rotatable about a respective axis, also has a built-in dust extraction device comprising an extractor hood located in close proximity to the spindle and presenting a suction port positionable near to a machining area, so as to extract chips and dust generated in the course of machining operations; the hood is capable of movement along a direction parallel to the axis of rotation, extended and retracted by the action of respective translating members operating in conjunction with sensors able to read the profile of a workpiece, in such a way that the suction port can be positioned to best advantage.