A data reading method for a rewritable non-volatile memory module is provided. The method includes receiving a reading command from a host system; identifying a target physical unit of the rewritable non-volatile memory module according to the reading command, and identifying a program erase cycle value, a first timestamp, a second timestamp of the target physical unit, wherein the first timestamp records a time at which the target physical unit is programmed last, and the second timestamp records a time at which the target physical unit is read last; and selecting a target reading voltage set among a plurality of reading voltage set according to the program erase cycle value, the first timestamp, the second timestamp, so as to read a target data from the target physical unit.