A memory system performing error correction of an address mapping table and a method of controlling the same are provided. A memory system includes a nonvolatile memory device, a dynamic random accessmemory (DRAM) configured to store an address mapping table for an access to the nonvolatile memory device, and a controller configured to store, in the DRAM, the address mapping table that is dividedin units of address mapping data, each of the units having a size of an interface of the DRAM, read, from the stored address mapping table, target address mapping data corresponding to a logical address that is received from a host, the target address mapping data including a target parity and physical addresses of the nonvolatile memory device, and perform an error correction on the read targetaddress mapping data, using the target parity.