A memory system of an embodiment includes a nonvolatile memory, a primary cache memory, a secondary cache memory, and a processor. The processor performs address conversion by using logical-to-physical address conversion information relating to data to be addressed in the nonvolatile memory. Based on whether first processing is performed on the nonvolatile memory or second processing is performed on the nonvolatile memory, the processor controls to store whether the logical-to-physical address conversion information relating to the first processing to be in the primary cache memory as cache data or logical-to-physical address conversion information relating to the second processing to be in the secondary cache memory as cache data.