The interest level estimation system of the present invention includes a gaze measurement unit that measures a person's gaze velocity and a skin potential level measurement unit that measures a person's skin potential level. The interest level estimation system also includes an interest level estimation unit. In the interest level estimation unit, a skin potential level time variation and a gaze velocity standard deviation are obtained at predetermined intervals, an inflection point of the skin potential level time variation is obtained at the predetermined intervals, the skin potential level time variation and the gaze velocity standard deviation that are obtained before a time corresponding to the inflection point are related to an interest state at the predetermined intervals, and the skin potential level time variation and the gaze velocity standard deviation that are obtained after the time corresponding to the inflection point are related to a disinterest state at the predetermined intervals, thereby obtaining a relationship between the skin potential level time variation and gaze velocity standard deviation and the interest level.
