Disclosed are an Intelligent electronic device and authentication method using message sent to intelligent electronic device. The method of authenticating using a message transmitted to the intelligent electronic device comprises the steps of: receiving a first message from a first external device; learning the received first message and extracting characteristics on a user of the first external device based on the learned first message; generating a template for the user of the first external device modeled based on the extracted characteristics on the user of the first external device; receiving a second message from a second external device; determining whether a unique identifier of the first external device is the same as a unique identifier of the second external device; and comparing the second message with the template to determine whether the user of the first external device is the same person as the user of the second external device, when the unique identifier of the first external device is the same as the unique identifier of the second external device. Accordingly, the fraud of impersonating another person can be prevented. The method of authenticating using a message transmitted to the intelligent electronic device of the present disclosure may be associated with an artificial intelligence module, a drone, a robot, an augmented reality device, a virtual reality device, a device related to a 5G service, and the like.