Surface alloying was carried out on molybdenum using continuous wave Nd : YAG and CO2 lasers. The alloying element (nickel) was deposited on the molybdenum surface by plasma spraying. Microstructure evolution and phase identification was investigated by means of optical and scanning microscopy and X-ray microanalysis. Layers with an average content of about 33% at. of nickel were obtained. Rapid solidification with fine scale microstructures and non-equilibrium nickel rich phases was reported. Molybdenum oxides with a suggested composition of the MoO2 were also identified. In addition the results of investigations of the alloyed layer microhardness and the layer resistance to erosion in an electric arc have been presented.