Disk access method

A disk access method is applied to a disk, wherein the disk is divided into a plurality of disk partitions adjacent to each other. When a partition start address of a disk partition is aligned with a minimum access unit, the disk access method accesses the disk partition directly by a predetermined access address. When the partition start address of the disk partition is not aligned with the minimum access unit, the disk access method divides the disk partition into a continuous displacement space and a shift space. Then, the disk access method converts the predetermined access address into a real access address according to the predetermined access address and an offset of the shift space and accesses the continuous displacement space or the shift space by the real access address. Accordingly, the disk access method can improve access efficiency and save disk space.