RDX is preferred as explosive in munitions due to its balance of power and sensitivity that is known to be dependent on its particle size and size distribution. In this study, we prepared nano-sized RDX in a silica xerogel matrix using a sol-gel method and investigated its sensitivity for explosive properties. The presence of RDX in composite xerogel was confirmed by TG-DSC and FTIR techniques. Microstructure and porosity were characterized by transmission electron microscopy (TEM), small angle X-ray scattering, and N-2-physisorption techniques. TEM results showed that the size of RDX particles in the RDX-silica composites is in the range of 10-30nm. The sensitivity to impact and friction was found to be higher for the composites compared to raw RDX. It was also found to be significantly dependent on the acetone/TMOS ratio used in the preparation.