To provide a two-face machining cast iron plate which can machine both of an end face and a peripheral face of a monocrystal diamond cutting edge by the single cast iron plate, and also to provide a two-face machining device and a two-face machining method.

According to the structure of the two-face machining cast iron plate for the monocrystal diamond cutting edge, the disk-shaped cast iron plate has conically inclined surfaces corresponding to an end face cutting edge angle and a peripheral face cutting edge angle of the monocrystal diamond cutting edge. The two-face machining device for the monocrystal diamond cutting edge machines the end face and the peripheral face of the diamond monocrystal cutting edge by applying minute diamond particles dissolved in olive oil or the like, to the disk-shaped cast iron plate, and by rotating the cast iron plate. The conically inclined surfaces corresponding to the end face cutting edge angle and the peripheral face cutting edge angle of the cutting edge are formed on the single cast iron plate, and the monocrystal diamond cutting edge is located at a location that is shifted in a y direction from an x-axis of the cast iron plate, so as to face the inclined surfaces.