Context <p>In this work, a strategy for solving the problems in an actual application of energetic materials like the safety and combustion problems was proposed. A novel kind of carbon material with much smaller size than the traditional one, that is the cyclo[n]carbons (C_<i>n</i>, <i>n</i> = 10, 14), was used to form energetic composites (HMX@<i>m</i>C_<i>n</i>, m = 1–4) with the representative compound (HMX) of energetic materials with high energy. The small size of cyclo[n]carbons may provide high flexibility for adjusting the carbon content in the energetic composites to better control the combustion behavior and energy-releasing efficiency. Our calculations show that C_<i>n</i> can form stable composites with HMX through different interactions synergistically. The electrostatic potential and electronic structure of HMX can be regulated by C_<i>n</i>, showing the potential for modulating the corresponding performance like the thermal decomposition and safety properties. For example, due to the effective reduction and dispersion of high-positive ESP, the anti-impact property of HMX was enhanced by C_<i>n</i>. Also, due to improvement in the electrostatic sensitivity values, the anti-static property of HMX@<i>m</i>C_<i>n</i> composites is much better than that of HMX. In all, based on the proposed strategy, various properties of formed HMX@<i>m</i>C_<i>n</i> composites may all be better than those of HMX, showing the multifunctional features. This study may provide a perspective for effectively solving the existing problems of energetic materials in practical applications.</p> Methods <p>All of the calculations on the structures were carried out by using the Gaussian 09 software at the M06-2X/6-311G(d,p)level. In addition, further calculations on the properties and interactions were performed by using the Multiwfn software.</p>