Abstract:The urban built-up area is the objective reflection of regional distribution of urban construction and development, and is the main area of smart city construction.In view of the characteristics of the urban built-up area, such as rich terrain information and large area. In this paper, technical method of using domestic fixed-wing mapping UAV to obtain urban high-resolution image data has been put forward. Rapid update of topographic map of the built-up area with the scale of 1∶500 has been completed, and the accuracy of the results has been tested. It is showed that this method has good applicability in rapid updating of geographic information in urban built-up areas.