Abstract: To study the coating on nitramine HMX filler surfaces, based on the data of coating degree from XPS measurements, tris (hydroxy methyl) propane was chosen as triol monomer when preparing OH terminated PU prepolymers, which enables the designed crosslinked coating polymer to improve the abrasion resistance and solvent resistance of the coatings. The emulsion polymerization of OH terminated PU prepolymer and isophorone diisocyanate was used to form the polymeric shell on nitramine HMX particle surfaces. A suitable processing technique for applying the coatings was developed in an emulsion system. The sufficiently coated HMX fillers were incorporated into an energetic composite. A 21 3% increase of tensile strength was obtained when compared to a similar formulation incorporating uncoated HMX. It is shown that the formation of crosslinked polymeric coating on HMX filler surfaces plays a role for interfacial reinforcement between HMX fillers and polymeric binders.