The efficiency of modification of the surface layers of Al–6Mg aluminium alloy by combined treatment, including electric discharge surface alloying (EDSA) with Tungsten and finishing ultrasonic impact treatment (UIT) to improve the microstructure, strength and corrosion properties is analysed. The results of electron microscopic and x-ray structural phase analyses indicate the formation of the surface layer containing Al–W solid solution and Al$_{4}$W or Al$_{12}$W intermetallic phases, which cause hardening. Micro-durometric analysis shows that the combined (EDSA (W) + UIT) process doubled the microhardness of the surface layers as compared to the initial state. As shown, the modified surface possesses the increased anti-corrosion properties owing to the accelerated formation of the passivating oxide film due to the large number of intergranular and interfacial boundaries.