Storage device, data protection method therefor, and data protection system

A data protection method for a storage device is provided, comprising the following steps: start-up step, monitoring step, and file access step. The start-up procedure includes: when a storage device is connected to a data interface of an electronic computing device, loading at least one kernel module of an operating system and accordingly starting a data protection program in the storage device. The monitoring step and file access step are performed by using the at least one kernel module and the data protection program. The monitoring step includes: monitoring any file to be or being accessed in the electronic computing device, a corresponding source program by which the file is to be or being accessed, and program module/sub-program(s) related to the source program, so as to determine whether there is any abnormality. The file access step includes determining whether to allow access to an encryption file in the storage device, wherein the encryption file, when being accessed, is monitored by the monitoring