A memory management method for a rewritable non-volatile memory module is provided. The method includes: selecting at least one first physical erasing unit from at least part of physical erasing units according to a first parameter. The method further includes: selecting a second physical erasing unit from the at least one first physical erasing unit according to a second parameter, wherein the second parameter is different from the first parameter; and copying at least part of data stored in the second physical erasing unit to a third physical erasing unit.