Abstract: In order to improve the capacity of weapons system to attack multiple targets precisely at the same time, the multi-target tracker can be used to assist laser and servo platform to capture and track multiple potential targets in electro-optical system. A novel multi-target detecting algorithm run in multitarget tracker was studied. According to the difficulty of processing timely in embedded system for the high resolution of digital image and mountainous data flow, based on TMS320C6455 digital signal processing (DSP), a global optical flow estimate image mosaic algorithm based on wavelet pyramid decomposition was proposed to achieve background compensation in moving image to get difference image.Compared to traditional block matching, gray-scale projection matching and key-points relevant matching algorithm, the new method is more accurate and timely running. Region growth combined with tunnel filter algorithm was carried out to acquire multiple final targets in difference image. The experiment verified that the method can achieve 95% detection rate and cost only 25 ms for automobile, bicycle and pedestrian in complex ground, which has good real-time performance and detecting effect.