The present invention provides a method for accessing a flash memory module is disclosed, wherein the flash memory module includes at least one flash memory chip, each flash memory chip includes a plurality of block, each block is implemented by a plurality of word lines, each word line corresponds to K pages, and each word line includes a plurality of memory cells supporting a plurality of states, and the method includes the steps of: receiving data from a host device; generating dummy data; and writing the data with the dummy data to a plurality of specific blocks, wherein for each of a portion of the word lines of the specific blocks, the dummy data is written into at least one of the K pages, and the data from the host device is written into the other page(s) of the K pages.