A flash memory device includes a memory cell array having a set-up data region configured to store set-up data, wherein the set-up data includes first data and second data. The second data is stored in an empty cell area of the set-up data region. The flash memory also includes a page buffer and decoder configured to read the set-up data from the set-up data region, and a status detector receiving the set-up data from the page buffer and decoder and configured to discriminate the first data from the second data and generate a Pass/Fail status signal.