A hair iron comprises of a pair of holding arms pivotally articulated at one end, operating holding action by grasping the hand hold part placed in the center of the holding arms. A pair of reformation plates is placed on the top side of the two arms with their reformation plane facing each other for straightening hair by holding hair in between the reformation plates with heat added by the heat plate. The reformation plates are movably held on the holding arms with a plurality of coil springs. The plurality of coil springs also pushes the reformation plates each other to their facing direction to control the state of holding hair. Thus the control of the contact pressure and also the control of the uniformity of the contact pressure over the reformation plane 87 can be facilitated.