A remote controller for controlling an external device by using voice recognition, the remote controller comprising: a microphone; at least one sensor; a communication interface; and a processor configured to control the microphone, the at least one sensor, and the communication interface, wherein the processor is further configured to: identify a user utterance intention based on utterance intention information of the remote controller and utterance intention information of the external device, the utterance intention information of the remote controller being based on a state of the remote controller or an external state identified by the at least one sensor, and the utterance intention information of the external device being received from the external device through the communication interface, wherein the utterance intention information received from the external device includes at least one of information about whether a pop-up guide for guiding a user to utter a voice is displayed on a display of the external device, information about a user utterance history corresponding to a content displayed on a display of the external device or information received from the external device includes information about whether a subsequent utterance of the user is predicted, control whether to supply power to the microphone according to a result of the identification of the user utterance intention, and control the communication interface to transmit an electrical signal corresponding to a voice of a user received through the microphone to the external device. a microphone; at least one sensor; a communication interface; and a processor configured to control the microphone, the at least one sensor, and the communication interface, wherein the processor is further configured to: identify a user utterance intention based on utterance intention information of the remote controller and utterance intention information of the external device, the utterance intention information of the remote controller being based on a state of the remote controller or an external state identified by the at least one sensor, and the utterance intention information of the external device being received from the external device through the communication interface, wherein the utterance intention information received from the external device includes at least one of information about whether a pop-up guide for guiding a user to utter a voice is displayed on a display of the external device, information about a user utterance history corresponding to a content displayed on a display of the external device or information received from the external device includes information about whether a subsequent utterance of the user is predicted, control whether to supply power to the microphone according to a result of the identification of the user utterance intention, and control the communication interface to transmit an electrical signal corresponding to a voice of a user received through the microphone to the external device. identify a user utterance intention based on utterance intention information of the remote controller and utterance intention information of the external device, the utterance intention information of the remote controller being based on a state of the remote controller or an external state identified by the at least one sensor, and the utterance intention information of the external device being received from the external device through the communication interface, wherein the utterance intention information received from the external device includes at least one of information about whether a pop-up guide for guiding a user to utter a voice is displayed on a display of the external device, information about a user utterance history corresponding to a content displayed on a display of the external device or information received from the external device includes information about whether a subsequent utterance of the user is predicted, control whether to supply power to the microphone according to a result of the identification of the user utterance intention, and control the communication interface to transmit an electrical signal corresponding to a voice of a user received through the microphone to the external device.