Application of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (HNIW) as an interested nitramine explosive has been developed during recent years. Since the particle size reduction of explosive improves its performance, in this study, Taguchi robust design was applied as a statistical method for efficient optimization of process parameters which are effective for tuning the particle size of HNIW powder prepared by SAS technique. The effects of different variables: temperature, pressure, HNIW concentration, flow rate of feeding solution, type of solvent, and surfactant on the size of produced HNIW particles were investigated under three different levels. By the aid of analysis of variance the effect of studied parameters on the size of prepared HNIW particles was evaluated. Analysis of variance revealed that the particle size of HNIW during SAS process could be tailored by tuning the effective parameters under their optimum levels. Meanwhile, optimum conditions for obtaining HNIW nanoparticles by SAS technique were determined. Performing the process under optimum conditions proposed by Taguchi method leads to producing HNIW nanoparticles with the average size of about 40 (+/- 9) nm. (c) 2013 Elsevier B.V. All rights reserved.