A non-volatile memory device including a non-volatile memory and a controller is provided. The controller establishes a standard table and at least one priority table according to a read table stored in the non-volatile memory. The probability that the controller utilizes the read voltages corresponding to the indexes recorded in the priority table to read and successfully decode the codewords stored in non-volatile memory is high. When the controller utilizes the read voltages corresponding to the indexes recorded in the priority table to read and unsuccessfully decode the codewords, the controller utilizes the read voltages corresponding to the indexes recorded in the standard table to read and decode the codewords stored in non-volatile memory.