The laser tracking system is widely used in the large-scale measurement field in industry providing accurate spatial information of measured objects. In this paper, the frame of software system for the laser tracker is introduced, as well as the design and implementation of each module. With the help of the software, customers can attain high precision measuring results within large volume. Functions of information communication, command control, error calibration and compensation, geometric element analysis and display can also be realized. The software system is divided into six modules, including the interconnect communication and on-line control module, error calibration and compensation module, data analysis module, database management module, 3D display of geometrical elements and man-machine interface. The design and construction of each module is described in detail which can help customers realize different functions throughout the measuring process.