A method for minimizing the degradation of performance upon accessing a flash memory using a logical-physical mapping scheme, and a method for efficiently storing and managing information on logical-physical mapping in a flash memory. A method for writing data in a flash memory includes determining whether a sector is empty in a physical page having a most recently written logical page number of data to be written, the offset of the sector matching that of the data to be written; if the sector is empty, writing the data in the sector to the physical page; and if the sector is not empty, selecting an empty physical page to write the data to a sector in the selected empty physical page of which the offset matches that of the data to be written and writing a logical page number for the data to the selected empty physical page.