Abstract: Spaceborne two-dimensional turntable is an important part of the laser communication pointing structure and one of the key components affecting the performance of the satellite-based equipment, which requires reasonable structural design and correct stiffness analysis, and the correctness of the design analysis is verified by comparing the test results with the simulation results. Firstly, the structural form of spaceborne two-dimensional turntable was introduced, two structural form of pendulum mirror assembly was compared and analyzed based on Isight integration and optimization method, the stiffness design of the U-shaped frame and shaft system was completed. Then, finite element modeling of the two-dimensional turntable was conducted and the spring unit equivalent modeling of the bearing was focused on. Finally, the stiffness analysis and test verification of the spaceborne two-dimensional turntable were carried out. The error between the natural frequency of the two-dimensional turntable in the X, Y, and Z directions of the simulation calculation and the test result was within 6%, indicating that the equivalent spring unit can accurately simulate the mechanical characteristics of the bearing joint. The dynamics test of the two-dimensional turntable shows that the mass constraint and stiffness requirements of the two-dimensional turntable are ensured, the structural stiffness of each component part is reasonably designed, and the mechanical resistance of the two-dimensional turntable meets the mission requirements of laser communication.