The features of the formation of Cu–Ni alloy films by electron beam evaporation are considered. The position of the isobars of the total pressure of copper and nickel on the state diagram of the Cu–Ni during evaporation in vacuum is determined. Calculations of the elemental compositions of films have been carried out. It is shown that the nickel content in films deposited during boiling of Cu50Ni50 alloy in vacuum is 50 times less than in the alloy. The structure and elemental composition of the surface layer of alloys after their evaporation and sublimation, as well as the elemental composition of the deposited films, are investigated. It is shown that the most acceptable way to obtain films of stable composition in the Cu–Ni system is simultaneous electron beam evaporation of copper and nickel from two crucibles.