A method for managing data stored in a non-volatile memory having a plurality of memory blocks includes, first, determining if an error occurs in the read data in a selected memory block. If an error occurs in the read data in the selected memory block, then a region to which the selected memory block belongs is determined. If the selected memory block belongs to a code data region, it is determined if the number of bit errors of the read data is less than or equal to an allowed number of bit errors. If number of bit errors of the read data is less than or equal to the allowed number of bit errors, the selected memory block of the code data region is replaced with a reserved memory block, and the selected memory block of the code data region is designated to a user data region.