A spectacles-type image display device provided with an image output unit that includes a display element for displaying images and a projection lens for magnifying and projecting the images and a reflection unit that is disposed adjacent to at least one of spectacle lenses and reflects the image light output from the image output unit toward the eyeball is provided. The reflection unit is a reflection member having no refractive power and an effective luminous flux that is output from the image output unit and reaches the eyeball is configured so that the width of the luminous flux perpendicular to an optical axis is minimum at the reflection unit with respect to the optical axis cross-section in at least one direction.