The objective of this study was to determine the best conditions to formulate solid lipid Nanoparticles using Glycery1 monostearate as lipid matrix which has advantage to be biocompatible and easily degraded in vivo. Different formulation factors were studied including lipid concentration and surfactant concentration and type. Different concentrations of Glycery1 monostearate were tested for feasibility of formulation of solid lipid nanoparticles. As the concentration of lipid increased from 1 t- 10 % w/w, particle size of produced particles was reduced to be in nanometer range. It was found that Tween 80 surfactant had produced smaller particle size than Tween 20 did. According to concentration of surfactant, it was found that increasing concentration from 0.5 %w/w to 5% w/w have pronounced effect on physicochemical properties of formulated solid lipid Micro/nanoparticles especially particle size. Reduction of particle size to be in micro/nanorange will enhance dissolution of drug and penetration of drug loaded particles through different body tissues. Besides that, lesser dose will be required that will reduce adverse effects and overall cost.