The present invention proposes a digital holographic display apparatus including a light generating unit configured to generate coherent light, a spatial light modulator configured to reproduce 3-dimensional hologram images on a space by modulating the coherent light, a vertical viewing angle magnifying unit configured to expand a vertical viewing angle by vertically steering a beam that forms the hologram images through a first mirror, a horizontal viewing angle magnifying unit configured to expand a horizontal viewing angle by steering the beam to top of a table through a second mirror, and a control unit configured to control the special light modulator, the vertical viewing angle magnifying unit and the horizontal viewing angle magnifying unit in order the hologram images to be formed on an observation space for hologram. Accordingly, by expanding the horizontal and vertical viewing angles of hologram images, an observer may observe the hologram images more comfortably.