According to one embodiment, a memory system copies content of a first logical-to-physical address translation table corresponding to a first region of a nonvolatile memory to a second logical-to-physical address translation table corresponding to a second region of the nonvolatile memory. When receiving a read request specifying a logical address in the second region, the memory system reads a part of the first data from the first region based on the second logical-to-physical address translation table. The memory system detects a block which satisfies a refresh condition from a first group of blocks allocated to the first region, corrects an error of data of the detected block and writes the corrected data back to the detected block.