The dispersion of ultrafine pulverized RDX (UFRDX) particles in water was studied by measuring the turbidity of the suspension colloids which had been precipitated for a certain time. The surface of some UFRDX particles was modified by adding several surfactants including ionic,nonionic,zwitterionic and composite surfactants. It is found from the results that nonionic surfactant OP and composite surfactants show a good modification effect,especially OP sodium dodecyl benzene sulfonate can OP-sodium dodecyl benzcne sulfonate can ~TeatlY improve the dispersion of UFRDX pmticles in water. The adsorption mechanism ofsurfactants on the particles and the stabilization mechanism of the poticles in water were also studied by measuring the potential of UFRDX particles.