To provide a structure for attaching a cutting height adjuster to a hair cutter with which a stress can be reduced in the case of attaching the cutting height adjuster to the hair cutter while keeping satisfactory accuracy in the finish of an object to be cut.

On the left and right terminal parts of a bottom wall 4 of the cutting height adjuster 2, crimping walls 6 are erected for crimping left and right outer faces 16d and 16e of the hair cutter 1. At positions close to the bottom wall on the front and rear terminal parts of the confronted inner faces of a pair of the crimping walls 6, pawl parts 7 are provided while being respectively protruded inwards. At positions close to a blade on the left and right outer faces 16d and 16e of the hair cutter 1, holding parts 8 are provided for fitting in the pawl parts 7. On the left and right outer faces 16d and 16e of the hair cutter 1, introducing groove parts 9 are recessed for introducing the pawl parts 7 into the holding parts 8.