This paper summarize basic theory, compute accerlate technology and application of building sunlight analyse CAD program. Such as compute the position of sun, large scale points analyse accerlation technology, It introduce some basic analyse methods based on local sunlight time-long compute stands, the represention of compute result, such as real-time drawing building shadows, sunlight analyse table and report. Above sunlight traditonal analyse areas, some extended areas, such as compute and utilitize soloar exposure energy, glass wall reflection and sunlight pollution, shading device design are also discussed in this paper. The methods and technologies discussed in this paper have been used in PKPM sunlight.