Disclosed is an image display device comprising: a communication unit for receiving, from a control device, a control command for controlling an operation of the image display device; a memory for storing at least one instruction; and a processor for executing the at least one instruction stored in the memory, wherein the processor executes the at least one instruction to: receive first user information corresponding to a control device user, and authentication state information indicating a user authentication state in the control device; and when the control command includes a request for an operation requiring authentication, perform authentication on the basis of the first user information, the authentication state information, and second user information corresponding to an image display device user, and perform the operation according to the control command.