The invention provides an optical disk library device and an optical disk device selecting method. In the optical disk library device, deterioration due to use frequency deflection of disk devices can be prevented. In the optical disk library device using a plurality of optical disk devices, before optical disk devices execute recording or reproduction of information to or from optical disks, self-monitoring information is acquired from an optical disk monitor, use preferential orders of the optical disk devices are evaluated on the basis of use frequency information or deterioration information included in the self-monitoring information and an optical disk device to be used for recording or reproduction of information is selected on the basis of the use preferential orders.