A memory controller having an improved operating speed controls a memory device in response to a request from a host. The memory controller includes: a processor for driving firmware for controlling communication between the host and the memory device; a map data receiver for receiving map data including a plurality of mapping entries including physical block addresses, for operations to be performed on the memory device from the memory device under the control of the processor; and a map data controller for checking a mapping entry corresponding to the request, which are received from the map data receiver, snooping the detected mapping entry and outputting the detected mapping entry to the processor.