Ballistic missile is a kind of high-performance offensive weapon.In the process of penetrationit will adopt a series of penetration technologies and form ballistic group targetswhich makes it difficult for our radar to track the target.Thereforehow to stably track ballistic group targets with high precision becomes the key to solve this problem.The idea of ballistic group target tracking is comprehensively introduced.According to the framework of ballistic group target trackingthe realization algorithms of each function unit are summarized.The basic principles and characteristics of the group initiation algorithmthe group combination/separation algorithmand the multiple target tracking algorithm with data association and data non-association are mainly expoundedand the development direction of ballistic group target tracking technology is described from four aspects.