Disclosed is a disk label printer that includes a slot-in type optical disk driving mechanism and a printing mechanism integrated with each other, has a small size, and smoothly transfers optical disks. The disclosed disk label printer includes: a case that has a slot through which an optical disk is inserted or ejected formed therein; an optical disk driving mechanism that is provided in the case and writes and/or reads signals to and/or from the optical disk mounted to a disk mounting portion; and a printing mechanism that is provided in the case and includes a thermal head which prints a desired image on a label surface of the optical disk. The printing mechanism is provided on a transfer path of the optical disk toward the optical disk driving mechanism between the slot and the optical disk driving mechanism. The thermal head and a platen roller come into pressure contact with each other with the optical disk interposed therebetween on the transfer path, only when the optical disk is transferred during the driving of the printing mechanism. The thermal head and the platen roller are withdrawn from the transfer path so as to be separated from each other, when the optical disk is transferred during operations other than the driving of the printing mechanism.