An iris authentication apparatus includes a camera for obtaining the image of an eye; a display panel arranged on the same plane as where the lens of the camera is arranged; and guide character generation means, wherein a guide character is displayed on a display panel, and the eye of a person to be authenticated who watches the guide character is guided. As a result, a satisfactory iris image can be obtained by the iris authentication apparatus of one camera type that does not have a zooming function, so that the iris authentication apparatus that can be mounted to a small body, such as a portable telephone, can be provided.