A series of Cu-W alloys added with Boron powder were prepared by means of powder metallurgy-infiltration process. The effects of Boron addition on the microstructure and properties of CuW alloys were investigated.The static properties, the vacuum breakdown property and the wear resistance were studied respectively. The results show that boron element and W were in-situ reacted and formed tungsten boride pahse in the sintering process of W skeletons. The hardness of the CuW alloy increases to 215HB owing to the strengthens of W skeletons. Meanwhile,the breakdown strength is increased by 63.2%, the chopping current is decreased 21%, and the coefficents of friction is decreased 32.7%, respectively. The wear resistance of the CuW alloys is enhanced significantlly. The metallographic analysis of CuW alloys after vacuum breakdown showed that the splash of liquid copper is decreased, the breakdown areas increase but the erosion pits become shallower and smaller.