[Problem] Providing a method, system and device for assisting diagnosis of autism which enable assistance of early detection and early definite diagnosis of autism (especially in infants) based on objective evaluation, using a conventionally suggested "eye-gaze detection technique".[Means to solve the problem] Provided is a method for assisting diagnosis of autism of a subject using an eye-gaze detecting unit, the unit having at least an imaging camera portion, the method comprising displaying, at the position in front of the subject along the direction of the eye gaze of the subject, an illusionary image contained in a plane of an illusion-causing image on a displaying device detecting eye-gaze position information of the subject looking at the plane inputting the eye-gaze position information of the subject into an eye-gaze position information storage portion and evaluating the eye-gaze positions of the subject using a predetermined algorithm for assisting diagnosis of autism, and the like.
