Data restore method of memory system including flash memory device

Here and flash memory devices; And it provides the read voltage setting method of the memory system including a memory controller for controlling the flash memory device, and the method by varying the read voltage variation in sequence step to read the page data from the flash memory device, respectively; Constructing a table of the dispersion sprayed read voltage corresponding to each read page number of data bits that represents the erased state of the page data and the read data from the flash memory device; Comprising: on the basis of the dispersion table, detecting scattered read voltage corresponding to the data bit number representing the available cell states of each of the peak of the memory cells; And a step of defining a new voltage reading with the detected scattered read voltage.