In the development of weapons, the current trend is to replace incombustible constituent elements with combustible ones. The traditional porous combustible objects are composed of nitrocellulose as energetic component, which is highly sensitive and inflammable. Formulations composed of high content RDX and inert polymer binder were employed to replace the tradional ones. This paper reports the fabrication process of microcellular combustible objects with skin-core structure using supercritical CO2 (SC-CO2) as foaming agent. The objects were foamed in designed foaming molds with expansion ratios of 1.1, 1.2 and 1.35. The influence of foaming temperature, saturation pressure, expansion ratio and RDX content on porous structure was investigated by scanning electron microscopy (SEM). Thermogravimetric analysis was conducted and the results revealed a two-stage decomposition process of RDX and binder. Performance in terms of heat resistance and moisture resistance was evaluated and compared with the traditional ones. A comparative study indicated that microcellular combustible objects are superior to traditional ones in respect of their survivability.