An embodiment of the invention provides a data information backup method and a data backup method and device. The data information backup method includes: intercepting a write request aiming at a disk; determining a to-be-visited target disk area corresponding to the write request, wherein the target disk area is at least one of the disk areas of the disk, and the disk areas are the basic units of the disk; changing the record identification, representing the target disk unit where the target disk area is located, in a data changing record corresponding to the disk into written identification, wherein the disk comprises a plurality disk units determined on the basis of the disk areas, the data changing record is pre-built in an internal memory and at least comprises the record identification and the disk units in one-to-one correspondence to the record identification. By the data information backup method, data information backup efficiency of the disk can be increased, and influence of the backup on the performance and continuity of operating business is lowered.