An ultra-hard material fixed to a cutting tool is formed into a cutting blade by electric discharge machining. The wire electric discharge machine has a rotating shaft to which the cutting tool is mounted, and has a touch sensor mounted to an upper wire guide. A measurement program is generated on the basis of a machining path instructed by the machining program. A machining program is regenerated from rotating shaft coordinate information and path coordinate position information obtained at measurement points, on the basis of the measurement program. As a result, a rake face position of the cutting tool can be accurately measured and a wire electrode can be positioned accurately with respect to that position during machining.