In electro-discharge machining by using an electro-discharge machining electrode of a Cu(Ag)—W(Mo) material, the machining speed, the electrode wear ratio, and the surface roughness of a work piece are improved. For this purpose, to the Cu(Ag)—W(Mo) material, borates of an element selected from a group (M3) consisting of Mg, Ca, Sr, Ba, Sc, Y, and lanthanide and an iron group metal are added by appropriate amounts. As the borate compounds, particularly, it is preferred to use borate compounds expressed by M32B2O5 and M3B2O4.