Supercritical antisolvent is one of the important techniques for the synthesis of nanoparticles. This process has different and unique advantages; producing fine particles with the same and narrow size distribution, controllability of particle size, high purity of particle without solvent,etc. Modeling of this process helps to identify effective parameters and howthey affect the particle design and size. Modeling results of SAS showed that increasing the temperature in the precipitation vessel produced smaller particles because temperature is an effective parameter on the growth mechanism. Increesing pressure lead to obtaining smaller particles. Modeling results indicated that increasing nozzle diameter lead to larger particles ,while on the other hand, increasing converging angle generated smaller particles. therefore,higher temperature and pressure in the precipitation vessel, lower nozzle diameter and higher converging angle of nozzle are recommended as the optimum operating and design variables for formation of smaller nanoparticles. Keywords: Supercritical antisolvent; Supercritical;Nanoparticearametric analysis