polyaniline/polystyrene (PAni/PS) composites were prepared in aqueous solution by polymerization of styrene and aniline in two-stages. Firstly, styrene polymerize using Ammonium persulfate (APS) as an oxidant in the presence of various surfactants such as poly (vinyl pyrrolidone) (PVP), hydroxypropylcellulose (HPC), poly (vinyl alcohol) (PVA) and surfactive dopant sodium dodecylbenzenesulfonate (DBSNa). In next stage, aniline polymerize using potassium iodate (KIO3) as an oxidant in the presence of PS latex. In addition, nanocomposites of polyaniline containing nanometer-size CuO (Copper oxide) and Ag2O (Silver oxide) were synthesized by a chemical method using DBSNa as a surfactant. Products were characterized in terms of particle size, conversion of monomer to polymer, morphology, chemical structure and glass transition temperature that were dependent on the type of surfactant and metal oxide. The chemical structure, morphology and glass transition temperature of product were studied by fourier transform infrared (FTIR) spectroscopy, X_ray diffraction (XRD), scanning electron microscopy (SEM) and differential scanning calorimetery (DSC).The results show that the type and concentration of surfactant, type of metal oxide and concentration of oxidant play a major role on the surface morphology and particle size of products. The size range of the PAni/PS and PAni/metal oxide composites was about 80-240 nm and 70-140 nm, respectively.