Aiming at the limitation of the current target tracking performance evaluation method of photoelectric theodolite, an improved video signal injection test method is proposed based on the advantages of traditional optical signal injection test method. Firstly, according to the planned trajectory of the target during the test, the spatial mapping relationship between the target and the optical axis of the theodolite is calculated, and the corresponding target image and background image are generated, which are projected to the photoelectric theodolite by the target simulator, so as to establish the database for target and background image respectively. Secondly, according to the spatial position of the target as well as the spatial mapping relationship between the target and the optical axis of the theodolite at each measurement time, the target image and the background image in the image database are called. The target image is blurred according to the relative motion speed of the target, and then fused with the scene image, and injected into the video processor of the theodolite, so as to realize the tracking performance test of the theodolite with no-delay signal injection. The experimental results show that, the proposed video signal injection test method can achieve the measurement accuracy of outfield evaluation. It not only makes full use of the advantages of traditional optical signal injection test method, but also effectively solves the problems of the target simulator's projection delay and the need to follow the theodolite. It provides a new and effective way for tracking performance evaluation of photoelectric theodolite.