The present specification relates to a smart controlling device capable of utilizing machine learning for voice recognition and a method of controlling therefor. The smart controlling device according to the present invention includes a receiver configured to receive an input including a command trigger, and a controller configured to detect one or more external display devices, select a display device of the detected one or more external display devices, cause a power status of the selected display device to be changed to a first state, and cause a response data corresponding to a first command data received after the command trigger to be output on a display of the selected display device.