An apparatus and a method of reducing a program selection time in an optical disc multi-changer by determining whether a disc is mounted on a disc mounting unit before it is determined whether the disc is chucked and a type of the disc is discriminated. The method of operating the optical disc multi-changer having a tray with disc mounting units, includes receiving a signal to determine whether a disc is mounted on a current disc mounting unit of the disc mounting units, outputting a command signal to move to a next disc mounting unit of the disc mounting units where the received signal indicates that no disc is mounted on the current disc mounting unit, and receiving a program selection signal where the received signal is received from all disc mounting units. Accordingly, it is possible to reduce a program selection time by determining whether the disc is mounted on the disc mounting unit before the disc chucking and discrimination of the type of the disc are performed.