Embodiments of the disclosure relate to a memory system, a memory controller and a meta-information storage device. By providing a memory device configured to store mapping information between a logical address and a physical address, a memory controller configured to control the memory device and control a memory area in which mapping segments including some of the mapping information are stored and a meta-information storage device configured to store meta-information on the memory area, it is possible to provide a memory system, a memory controller and a meta-information storage device capable of processing a command received from a host as quickly as possible even when an SPO occurs.