As an important branch of visual reality technology, augmented reality has been applied to vast fields like commerce and education. This paper verifies the feasibility of applying augmented reality technology to the planning of residential district. A visual district planning system is designed and realized on the basis of augmented reality. It fully reflects the advantages of augmented reality technology in the application to district planning by meeting the requirements of district planning for visual-real interaction and man-machine interaction. This paper further describes visual-real registration technique based on computer vision and adopted by the system. Moreover, the results of system operation are given.