Insensitive explosives are a kind of explosives with low sensitivity to thermal stimulation, mechanical stimulation and shock wave, including insensitive pure explosives and composite explosives，which are key materials to improve the safety of ammunition. The explosives commonly used for filling weapons and ammunition are composite explosives with pure explosive as the main component (filler), polymer as the continuous phase, or molten energetic compounds (such as trinitrotoluene, dinitrobenzene methyl ether, etc.) or hot-melt wax as the carrier. Polymer bonded explosive (PBX) is the mainstream product for the development of insensitive composite explosives , which is widely used in modern weapons and ammunition. The sensitivity characteristics of insensitive PBX are closely related to their multi-scale structures, mainly including three levels of multi-scale relationships between sensitivities and their corresponding molecules, crystals and compounds, i.e., molecule structure and stability, crystal quality and stacking mode, and composites composition and its structures. As a result, the main ways to obtain both high-energy and insensitive explosives are developing multi-scale system design, structure regulation and preparation of insensitive explosives, to be specific, including the design and synthesis of insensitive energetic molecules, the design and regulation of crystal structures and its high-quality crystal desensitization technology, the application of high-efficiency desensitization technology based on loading and heat dissipation mechanisms and the research of structure-performance relationships of PBX. Strengthening the design and research of supramolecular explosives and eutectic explosives and the research of high-quality crystal desensitization for third-generation pure explosives are important directions for the development of high-energy insensitive explosives.