A first device is installed at a first location in a first space visible to a user. A second device is installed at a second location in a second space not visible to the user. A device control method acquires line-of-sight information indicating a line-of-sight direction of the user from a camera. The line-of-sight direction of the user is determined based on the line-of-sight information. In a case where the line-of-sight direction indicates a third location other than the first location, the second device is identified as an object of control. Sound data indicating speech of the user is acquired from a microphone, a control command corresponding to the sound data is generated, and the control command is transmitted to the object of control.