In order to realize high-precision measurement of spatial dynamic angle, a spatial dynamic angle measurement method based on machine vision is proposed. A high-precision two-axis servo system is installed onto the measured target. When the spatial angle of the measured target is changed, the servo system outputs the pitch angle and the azimuth angle by identifying and tracking the cooperative target。According to the spatial coordinate system transformation，the angle change value of the measured target can be obtained. The measurement accuracy of the spatial angle will be influenced by the accuracy of the tracking cooperative target with the servo system. A cross-patterned target board is designed based on the measured distance and the imaging system. Several major algorithms of detection are summarized. Their merits and demerits are analyzed by identifying and locating the center of captured image. The captured images are compared by the servo system controlled with these algorithms. The measurement results are solved by spatial coordinate transformation. According to the experimental results, a fast detection algorithm of target center in the real-time image processing is selected. High accuracy and good real-time performance of this method in processing the target image is demonstrated by calculating and comparing the results of each image processing algorithm, which satisfies the measured requirement of space dynamic angle.