A high-precision laser tracking system based on a two-dimensional galvanometer and position sensitive detector is proposed. A geometrical optics model of the tracking system is established using the ray tracing method, and error analysis is performed to simulate positioning precision and tracking performance of the proposed laser tracking system. Simulation results demonstrate that, when the target is located at a distance of 100 m, the tracking system's point position precision is 0.35 mm, angular precision is 0.72″, tracking range is -10° to 10°, and maximum tracking speed is 3.6 rad/s. These results indicate that the system can realize high precision and real-time active detection tracking for fast moving targets at long distances.