10 and 20 vol% Al2O3 particulate 6061 Al alloy composite sheets have been successfully joined by friction stir welding. Al2O3 particles were uniformly distributed in the stirred zone. Tensile test results showed good mechanical properties. Effect of the FSW conditions of tool rotation speed and welding speed on the formation of the good FSW joint was investigated in comparison with 6061 Al alloy. The optimum FSW condition range became narrower with increasing volume fraction of Al2O3 particles.