Dispersion strengthened copper-base composites Al2O3/Cu were fabricated by mechanical alloying and spark-plasma sintering. The effect of the content of rare earth La on the microstructure and properties of Al2O3/Cu composite powder and the sintered materials were studied. The results show that 0.05%La addition to the Al2O3/Cu composite powder accelerates grain refinement and alumina particle dispersion in the mechanical alloying process, so as to improve the microhardness and tensile strength of the composites. The conductivity of the composite increases and then decreases with the increase of the content of La, and the conductivity increases by 11.3%IACS when the La content is 0.10%.