Automatic reconstruction method for disk redundancy array device

Disclosed is a method for re-establishing RAID device automatically. The RAID device comprises plural member hard disks for one storage device which includes plural hard disks positions for setting plural hard disks. The method comprises following steps of: reading the configuration information of the storage device, in the configuration information having a hard disk position for re-establishing automatically; requiring the status information of the storage device; refreshing the storage device configuration information according to its status information; according to the configuration information of the storage device, when having one degrading member hard disk in the RAID device, adding one new hard disk to the hard disk position for re-establishing automatically, and re-establishing the RAID device.