To provide a method for storing data in a flash memory and a method for reading data out of the flash memory which make the frequency of erasure small and prolong the life of the memory.

With flags added to every record being data of minimum units of writing or reading, it is confirmed whether or not the data are written (step 102) for every address and writing is performed from an address where the data is not written (step 112). On the other hand, this method for writing data to the flash memory decreases the frequency of erasure by erasing object memory areas of data writing corresponding the the size of plural records collectively at a time (step 108) unless there is an address where no data is written.