Abstract: For the increasingly higher requirements of land navigation systems for the modern military vehicles, such as mobile silos, command stations, scout vehicles and so on, a new approach of position and azimuth determination for land vehicles was presented utilizing the angle information to three known landmarks measured by the electro-optical detection system which was mounted on the roof of the vehicle. Computer simulation results indicate that the position and azimuth of land vehicles can be accurately determined only based on once measurement information of each landmark by the electro-optical detection system, both estimation errors of vehicle position along east- and north-axis are mostly less than 0.5 meters, and the azimuth angle error can reach 20 arcsec (1σ). Besides high accuracy, the approach proposed is simple and quick, and it is capable of serving several land vehicles at the same time, hence it is of great value in practice.