This paper has introduced a kind of design method for digital urban lighting, it is an application of the illuminating engineering in digital city and a kind of measurable, dynamic visualization design method of the effect of digital urban lighting. A kind of new artificial method of scene imitation has been proposed in this paper. After taking pictures by verified digital camera, the luminosity and color information are taken to imitate the effect of urban lighting design, to display the current and future effect of lighting for the scene and thus optimize the urban lighting design plan to meet the demand of energy - conservation and beautifying the urban night scene.