Ultra-fine 2,2′,4,4′,6,6′-hexanitorstilbene(HNS-IV) was prepared by using solvent/anti-solvent recrystallization method. The effects of solvent factors,drying methods and process parameters,such as different solvents,anti-solvents,washing solvents,temperature,drying methods on the particle size,particle size distribution and morphology of HNS,were investigated. Results show that suitable solvents as follows: dimethylformamide(DMF) was solvent,and H₂O was anti-solvent and methanol was wash solvent. The particle size and size distribution can be controled by verifying the amount of solvent,amount of anti-solvent,amount of surfactant,temperature and drying methods. Crystal appearance of HNS is smooth with particle size from 0.5 μm to 1.0 μm.