In the use of carbon fibre reinforced plastics (CFRP) it is often necessary to cut the components, but cutting CFRP is often made difficult by delamination of the composites and by the short tool life. In this paper, the machinability of CFRP by means of ultrasonic vibration cutting was experimentally investigated. The experimental results have led to a trial application of ultrasonic vibration cutting, which has been verified experimentally to be highly effective in view of cutting force and surface quality.