Judgment method for WORM appending writing and storage device

The embodiment of the invention provides a judgment method for WORM appending writing and a storage device, and relates to the field of communication. The judgment method can more accurately judge whether writing operation of a WORM file is the appending writing or not. The method includes the steps in detail that an initial pointer position of the writing operation is obtained; a WRITE instruction sent by user equipment is received and carries a data size of the writing operation; according to the WRITE instruction, the writing-in range of the writing operation is identified; whether the protection range of the WORM file and the writing-in range of the writing operation has an intersection or not is detected; if the intersection is detected, whether data of the writing operation are the same as data of the intersection part between the writing operation and the WORM file or not is detected; if yes, the writing operation is judged to be the appending writing; if not, the writing operation is judged to be modification writing.