To provide a hair iron which can change bending degree of the hair curled by the single hair iron.

The invented hair iron 1 includes a pair of grips 9 which have base ends connected so that they can rotate and freely open/close, and heating parts 11 which face each other at the leading ends of each grips 9. The opposed surfaces of respective heating parts 11 are plane, curling parts 13 which form curvature are attached to the rear faces of the heating parts 11 and at least one of the curling parts 13 is attached with an auxiliary case 15 which has a curving face of the curvature different from the curvature of the curling part 13.