To provide an image display device which achieves the downsizing over the entire part by having three-dimensional eccentric optical paths and enables various designs by effectively arranging dead spaces.

The image display device having the three-dimensional eccentric optical paths includes an image display means 3 and an observation optical system which introduces the displayed images thereof to the pupil 1. This observation optical system has at least first reflection surfaces 24 and second reflection surfaces 22 arranged nearer the pupil 1 side on the optical paths than the first reflection surfaces 24 and is constituted to such an optical system which forms the three-dimensionally offcentered optical paths by first planes formed, by the intersection at an arbitrary angle, of the incident optical axes and reflection optical axes to and from the first reflection surfaces 24 and second planes formed by the incident optical axes and reflection optical axes to and from the second reflection surfaces 22. At least one surfaces among the first reflection surfaces 24 and the second reflection surfaces 22 are formed of a curved surface shape.