Si-C-N-O amorphous films were fabricated at about 800°C by pyrolysis of poly- vinylsilazane precursor films in a vacuum oven under N2 flow. The polymer precursor films were prepared onto Si wafers by spinning from a solution of the polymer. The compositions of the as-prepared films were confirmed by X-ray diffraction, Fourier transformation infrared spectroscopy, and x-ray photoelectron spectroscopy. SEM analysis indicated that the films can be formed with thickness more than several micrometers, and very smooth surfaces. Such films will be promising in application of protecting equipments in high-temperature, corrosive and wear environments.