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Al2O3 particle reinforced Mo composites were prepared by a sol-gel technique. The micro-hardness of the molybdenum matrix of the composites was determined, and the microscopic analysis of the mixed powder and the sintered billet were carried out by XRD, SEM and TEM. The sliding wear performance of the composite materials was measured by a pin-disc friction and wear testing machine. Results show that in the composite materials Al2O3 as disperse phase can refine the grains. The micro-hardness of the molybdenum matrix increases with the increasing of volume fraction of Al2O3 and the friction coefficient of composites decreases slowly. Meanwhile, the wear mass-loss first increases and then decreases. Therefore, the Al2O3 particles help to improve the abrasion performance of molybdenum matrix material.