A capper head for general purpose usable even when the specifications of a cap including thread pitches are changed without using a fixed gear and a lifting cam determining a lifting stroke and the timing thereof. The rotational output of a servo motor (2) is transmitted to a screw mechanism (4) through a sliding engagement section (3), and a screw shaft (17) is lowered while rotating for capping. The lowering stroke of the screw shaft (17) is allowed by the sliding engagement section (3). In capping, even if the strokes of a rotating chuck (7) and an output shaft (31) are different from the lowering stroke by the screw mechanism (4), a stroke difference absorption section (5) absorbs the stroke difference therebetween since a spring (23) in combination with a spline transmitting the rotation is deflected in the axial direction.