Abstract: In order to obtain the image and the position information of the target, an azimuth measuring method for moving targets based on monocular vision system is investigated. According to the principle of projection imaging, the mapping relationship between the 3-D position and the 2-D image of the target is derived, and the target azimuth measuring mathematical model is established based on monocular vision system. A detection combination algorithm is proposed using image subtraction and KLT method for moving targets under still background and changing background, and the sub-pixel orientation method is applied to the positioning of target feature points. The experimental and simulation results show that the method can extract the target feature points effectively, achieving a relatively accurate target positioning, and the target azimuth information is measured through monocular vision method, with the error within 8%.