The laser tracking testing platform is a spatial large-scale coordinate measuring instrument. The machining and assembly of the shaft system is the base for achieving high-precision measurement of the entire machine. To improve the pointing and positioning accuracy of the laser tracking platform, a laser tracking platform driven by an ultrasonic motor is developed, and a method for evaluating the pointing accuracy of the platform is proposed based on structural error modeling and analysis. Firstly, the platform′s topological structure is established based on the principles of multi-body system theory and coordinate transformation. Secondly, the shafting perpendicularity, coaxiality, feature position deviation, laser module assembly error, and the initial position of each static error are incorporated into the error transfer matrix. Meanwhile, considering the platform′s rotation, dynamic errors such as bearing vibrations and control errors are also incorporated. A well-comprehensive pointing error model of the platform is formulated. Based on the established model, numerical simulation experiments are carried out to quantitatively analyze the influence of each error, as well as the influence of the initial position of the error on the precision of pointing. Building upon the established model, numerical simulation experiments are performed to quantitatively assess the impact of each error on pointing accuracy and the effect of error initial positions. Finally, based on the simulation results, a laser tracking platform driven by ultrasonic motors is manufactured. Axis accuracy and pointing accuracy testing experiments are conducted. The experiments show that the platform has a wobbling of under 2. 2″ for both axes, with an angular measurement error of less than 1. 1″. At a distance of 6. 8 meters, the laser endpoint exhibits a repeat positioning error of less than 0. 20 mm in the Y direction and below 0. 42 mm in the Z direction. The experimental results validate the theoretical analysis process and demonstrate the effectiveness of the proposed method.