Abstract: The graphite oxide poly (diallyldimethyammonium chloride) ultra thin film was prepared by molecular deposition technology. Its structure was analyzed using an ultraviolet spectrometer and a Fourier transformation infrared spectrometer. The morphology and nanotribological properties of the film were investigated using an atomic force microscope. As the results, the GO PDDA ultra thin film obviously lowered the friction coefficient of the glass substrate, which might be attributed to the lower shear strength of the film as compared with that of the glass. The friction coefficient of the film decreased with increasing load, while the increase of the surface roughness of the film with different layer numbers led to increased friction coefficient.