PURPOSE: To eliminate a housing part and a transfer means for small diameter disk exclusive for housing and transferring a small diameter disk by providing a disk adapter transferred with the transfer means between a large diameter disk placing surface and a large diameter disk housing part.

CONSTITUTION: A magazine 1 housing a 12cm CD being the large diameter disk is provided on a chassis 2 vertically movably. Multistage of horizontal shelves housing the CDs are provided in the magazine 1 integrally, and the 12cm CD is housed on an upper shelf, and an 8cm small diameter CD is housed in the disk adapter A on a lower shelf. The magazine 1 is moved vertically, and the reproducing CD is moved to a position of a slider S. The slider S is provided on a palette P movably. When a pinion 3 engaging with a lack 2 formed on the side surface of the slider S is rotated counterclockwise, the slider S is advanced forward. The slider S is abutted on the front surface panel 41 of the palette P, and the CD is transferred to a reproducing position, and is placed on a large diameter disk placing surface 42. The transferring of the adapter A of the small diameter CD to the reproducing position is performed similarly.