A memory controller and an operating method of a memory controller are provided. The operating method includes detecting that a bus of an external host connected with the memory controller enters a first power saving mode; entering a second power saving mode of the memory controller according to a result of the detecting; detecting a wake-up process of the bus of the external host; and waking up the memory controller while the bus of the external host executes the wake-up process. The waking up of the memory controller is ended before the wake-up process of the bus of the external host is completed.