Structural factors and functions of cylindrical atomic distribution in superficial monolayers and in deep layers of Cu-Au melts are determined from electron diffraction by reflection of drop surfaces. It follows from comparison of structural factors that the superficial layer is more dose to ideal solutions than adjacent deep layers. The melt has dense packing with various species of atoms statistically distributed. Interatomic distances Cu-Cu, Cu-Au, Au-Au contribute to the first peaks of differential functions for cylindrical distribution of atoms. These average distances are shown to be more short at the surface compared to them in the depth. Superficial microstructures of the alloys are dose to packing with statistic distribution of atoms.