An image display apparatus includes a screen, a reflection mirror, an adaptive optics, and a projection unit. The reflection mirror has a reflective surface facing a light incident surface of the screen, and is separated from the light incident surface by a space. The boundary of the space is defined by the edges of the reflective surface and the light incident surface. The adaptive optics is disposed on the boundary of the space. The projection unit is disposed outside the space. The adaptive optics has a light exit side facing the reflective surface of the reflection mirror, and a light incident side facing the projection unit. A projecting light is generated from the projection unit, passes through the adaptive optics for adjusting the image size formed by the projecting light, and then is projected to the reflective surface of the reflection mirror for being reflected to the light incident surface.