The hair clipper of the present invention includes an adjusting device for adjusting a clipping height. The adjusting device includes an attachment, a handle ring, and a connection mechanism. The attachment is allowed to move in a predetermined moving direction relative to a blade block. The handle ring is allowed to rotate around a rotation axis extending along the moving direction. The connection mechanism moves the attachment with rotation of the handle ring. The connection mechanism includes a cam groove and a linking pin allowed to move along the cam groove. The cam groove includes a first side and a second side opposite to each other. The first side includes: plural step parts which are formed in different positions in the moving direction and extend in a direction perpendicular to the moving direction; and a slope part configured to connect the step parts.