To provide a cutting device and a cutting method which cuts even an extremely heteromorphic cutting object 1.

This cutting device is furnished with: two heads 3 supported free to revolve around a head rotation axis 2 arranged at a symmetrical position around a rotation central axis of the cutting object; disc type cutters 4 mounted respectively in two, each free to rotate within the same surface at positions with the same distance from a shaft center of the head rotation axis 2 and to cut the cutting object 1 from its circumference; and a head supporting mechanism to support a head supporting member 6 to support the head rotation axis 2 while energizing it to the rotation central axis side. The two cutters 4 mounted on each of the heads 3 are mounted free to change the distance between the cutters 4. In this constitution, even the extremely heteromorphic cross-section shape cutting object and the cutting object extremely different in size of outer peripheral diameters can be cut.