Digital three-dimensional imaging the photosensitive device for the diffraction grating and the photosensitive material is pressed to be mounted on a photosensitive platform (8), the photosensitive platform is connected to the base plate through the platform moving mechanism, the mechanism 7, the liquid crystal monitor (2 which is located above the photosensitive platform ), and it is arranged a lens which is located above the photosensitive platform through the lens moving mechanism, and here a diffraction grating (5) in the photosensitive platform, the lens is disposed on the lower liquid crystal monitor. This also provides the outside, a digital three-dimensional imaging method. The invention does not require a photosensitive paper after the composite diffraction grating and the photosensitive material, after the projection, is photosensitive can be to remove the photosensitive material and the diffraction grating, may be typical developing device is used for the developing. Moreover, this is not a double film of a film from the photosensitive material to be synthesized by the conventional method requires at the time of projection, the photosensitive, the color contrast of the stereoscopic image is superior to the color contrast in the art that the composite diffraction grating and the photosensitive material before projection.