Memory system and wear leveling method thereof

PURPOSE: A memory system and a wear leveling method thereof are provided to prevent a bad page from occurring on an NVRAM(Non-Volatile RAM(Random Access Memory)) by performing a wear-leveling operation when using the NVRAM as the main memory thereof. CONSTITUTION: A memory system(100) comprises a control unit(110), a main memory(120) and a non-volatile memory(130). The control unit includes an MMU(Memory Management Unit)(112), a memory allocation unit(114) and an APF(Aging Page Fault) handler(116), and stores aging information fro each page before turning off power and performs memory allocation for the main memory based on the aging information. The non-volatile memory is used to store data, and the data stored at the non-volatile memory are not deleted even when power is not supplied to the memory system. The data stored at the non-volatile memory are loaded to the main memory and processed by the control unit.