In order to reduce the guidance error of a satellite/inertial integrated navigation system and improve its navigation and positioning accuracy, a new navigation system scheme combining position sensitive detector (PSD) laser guidance with airborne satellite/inertial integrated navigation system was proposed. In this system, 1064nm infrared pulse laser was used as the guiding light source, and the combination of satellite/inertial navigation in the middle flight segment and laser guidance in the terminal flight segment was adopted. Through theoretical analysis and comparative experiments, the results show that the system always maintains high positioning accuracy and consistent results in the outdoor flight environment and the indoor strong, weak and normal lighting flight environment. Compared with the other existing guidance methods, the detection frequency of the system always remains 5kHz, and the positioning accuracy always keeps its circular error probable at the order of 0.10m. Good positioning experimental results are obtained. The system has the characteristics of strong robustness, simple circuit, flexible detection, high speed and precision. It is of great importance to the terminal guidance of unmanned aerial vehicle.