A disk anti-copy system. An encrypted anti-copy mechanism with a device key table (Kd Table) prepared in a device and a fixed encryption processed media key block (MKB) pre-recorded in a disk is established. Only through the appropriate fixed encryption process between the key and the MKB can the device correctly read the disk. This controls the device and prevents disks from being copied. Moreover, the invention provides a method and device for preventing disks from being copied.