In order to solve the problems of the complex optical multi objective group’s detection and tracking, presented an extended group-target concepts and multimode detection and tracking method. Analysis of extended group-target’s characteristics of complex form, many number of individual target, change quickly, detection and tracking difficult , and its requirement of detection and tracking. The detection algorithm of small target, extended target, high contrast and multi frame difference detection algorithm to complete the entire field-of-view target populations in the intact detection. Then based on the judgment of target′s trajectory coincidence with its practical position and the predicted position to realize target′s multi-feature track association, combined with contrast tracking, correlation tracking as a supplement to the main and auxiliary type multimode tracking technology to realize group-target′s tracking. The application results show that, extended group-target multimode detection and tracking method for complex multi target group detection efficiency, tracking accuracy were greatly increased, to meet the requirements of complex optical target group′s integrity detection and accurate tracking.