To effectively carry out a hair-cutting, and apply pin curls and perma nent waves to hairs by treating the hairs in such a manner as a three- dimensional way.

Hairs are treated in such a manner as a three-dimensional way to carry out a hair-cutting and apply pin curls and permanent waves to the hairs. Namely, while tension is applied to the hairs 12 in a slice base to be treated, the ridge of a comb 10 is located near to the root slice line of the slice base. When the comb 10 is substantially partly rotated, the comb 10 is rotated to raise the roots of the hairs on the slice base so that all the hairs on the slice base are housed in the comb 10 to comb the hairs 12. Further. the comb 10 is rotated until the comb 10 rotates substantially once, and the hairs 12 are combed to their tip ends to raise the hairs 12.