MAPPING TABLE UPDATING METHOD, MEMORY STORAGE DEVICE AND MEMORY CONTROL CIRCUIT UNIT

A mapping table updating method, a memory storage device and a memory control circuit unit are provided. The method includes: receiving a write command; recording physical-to-logical mapping information of write data corresponding to the write command into a first mapping table in a buffer memory; storing the physical-to-logical mapping information of the write data into a physical unit in a rewritable non-volatile memory module according to the first mapping table; updating the physical-to-logical mapping information of the write data recorded in the first mapping table, where the updated physical-to-logical mapping information only includes partial information of the physical-to-logical mapping information; and updating a second mapping table according to the updated physical-to-logical mapping information recorded in the first mapping table. Accordingly, the usage space of the first mapping table may be saved.