In this study, polystyrene-clay nanocomposites (PSNC's) were prepared via in-situ bulk and in-situ emulsion polymerization. The effect of organoclay and the architecture of surfactant were investigated. For the investigation of the effect of surfactant, organoclays were synthesized containing clay modifiers having different structures. Trimethylhexadecyl ammonium chloride, dimethylbenzylhexadecyl ammonium chloride and dimethylbenzyl(4-vinyl) hexadecyl ammonium chloride, which is synthesized in laboratory, modified clays were synthesized. Pristine polystyrene (PS) was synthesized by bulk and emulsion polymerization for comparison, and PSNC's containing 3 wt.% organoclays were prepared by both these polymerization methods.