The influence of three factors, such as volume percentage of reinforcement particles(i.e. Al2O3), tool tilt angle and concave angle of shoulder, on the mechanical properties of Cue Al2O3 surface composites fabricated via friction stir processing was studied. Taguchi method was used to optimize these factors for maximizing the mechanical properties of surface composites. The fabricated surface composites were examined by optical microscope for dispersion of reinforcement particles. It was found that Al2O3 particles are uniformly dispersed in the stir zone. The tensile properties of the surface composites increased with the increase in the volume percentage of the Al2O3 reinforcement particles.This is due to the addition of the reinforcement particles which increases the temperature of recrystallization by pinning the grain boundaries of the copper matrix and blocking the movement of the dislocations. The observed mechanical properties are correlated with microstructure and fracture features. The influence of three factors, such as volume percentage of reinforcement particles (ie Al2O3), tool tilt angle and concave angle of shoulder, on the mechanical properties of Cue Al2O3 surface composites fabricated via friction stir processing was studied. Taguchi method was used to optimize These factors for maximizing the mechanical properties of surface composites. The fabricated surface composites were examined by optical microscope for dispersion of reinforcement particles. It was found that Al2O3 particles are dispersed dispersed in the reinforcement zone. The tensile properties of the surface composites increased with the increase in the volume percentage of the addition of the reinforcement particles. this is due to the addition of the reinforcement particles which increase the temperature of recrystallization by pinning the grain boundaries of the copper matrix and blocking the movement of the dislocations. The observed mechanical properties are correlated with microstructure and fracture feat ures.