Abstract.  Radiofrequency plasma discharge is a convenient thin film deposition process, as it facilitates the synthesis of polymer films with stable physical and chemical properties suitable for various applications in microelectronic, optical and biomedical fields. The unique properties of these plasma polymerized films as compared to the conventional ones are strongly related to the proper adjustment of the external discharge parameters and selection of suitable monomer. It is also important to study the fundamental chemistry of RF plasma polymerization process, so that one can successfully correlate the internal features of the discharge with films properties and explore their possible technological applications. Polystyrene films having thickness in the range of 900 – 1800 nm are deposited from radiofrequency (RF) Ar/styrene glow discharge. Depositions of the films are carried out at working pressure of 1.2X10^-1mbar and in the RF power range of 40 – 130 W. Optical emission spectroscopy (OES) studies on Ar/styrene glow discharge reveal that the relative concentrations of active plasma species are strongly dependent on the variation of RF power. The physical and chemical properties of the polystyrene films are investigated as a function of RF power. Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) are used to analyze the internal chemical structures of the polystyrene films. The thermo gravimetric analyzer (TGA) and gel permeation chromatography (GPC) results suggest the presence of both highly branched aliphatic and aromatic units in the polystyrene films. Attempts are made to correlate the results obtained from OES, FT-IR and XPS analyses with the physico-chemical properties of the films. The possibility of using polystyrene films as protective coating is also explored.