In the current research, Surface nanocomposite containing graphene oxide performed on the surface of 5083Al alloy was investigated by using of friction stir processing (FSP) and microstructure, mechanical and tribological properties were evaluated. For this purpose, the friction stir processing with 315 rpm rotational speed 20 mm/min linear speed 2 degrees tool angle relative to the vertical axis were performed on the base alloy. Since the application of this process caused severe grain refinement from the first pass in all samples, the number of passes was introduced as an influential parameter. After the third pass, which determines the optimal pass, the effect of reinforcement intensity on the microstructural, mechanical, and wear behaviorwere studied. For this purpose, after creating depth of 2 mm and the width of 1mm grooves on the surface of the alloy samples that contain the reinforcement particles of graphene oxide with the values of one, three, five and seven percent, friction stir process was performed and The surface nanocomposites were created. Comparison of the base metal, bare processed sample, and nanocomposite processed for three passes, showed the highest increase in hardness and ultimate tensile strength in the sample which has five percent reinforcement. In order to determine the effects of the surface properties of samples, reciprocating wear test performed on base metal and nanocomposites for three passes and their wear behavior were studied by scanning electron microscopy. The results of these investigations showed that the dominant mechanism of wear has been adhesive wear. In addition, the sample with five percent reinforcement had the highest wear resistance and the base metal sample had the lowest wear resistance. SEM images of the failed surface of the base metal and processed samples containing reinforcement particles indicated that ductile failure is occurred in all samples. Keywords: Nanocomposite, Friction Stir Processing, Graphene Oxide, Wear, Hardness, Tensile