Provided is a storage device which communicates with a host device and configured to set a secure mode of a plurality of commands different in kind. An operating method of the storage device includes receiving a secure request indicating a protection of a first command and a protection of a second command of the plurality of commands, from the host device; setting a secure mode of the first and second commands, based on the secure request; receiving a first request indicating a request to execute the first command, from the host device; outputting a first response indicating failure of the first command to the host device, based on the first request; receiving a second request indicating a request to execute the second command, from the host device; and outputting a second response indicating failure of the second command to the host device, based on the second request.