The invention provides a hard disc data read/write quick access device and a method thereof. The device comprises a hard disc, a quick access control unit and at least a flash memory. The quick access control unit is connected with the hard disc and the flash memory to control and layout the flash as the hard disc data read/write quick access device. The method defines and set a management list to manage each corresponding data read/write logic block address of the flash memory, manages the EMS memory's access actions for reading or writing data in hard disc in virtue of a quick access data read step and a quick access data write step, reclaims, clears and displaces hard disc read/write quick access data and memory space by step of a quick access space reclaiming and displacing quick access temporary storing data, prevents the flash memory from losing and damaging the management list elements caused by power off or abnormal shutting to re-build management list to provide the flash memory with data read/write quick access control on hard disc.