Alloying Al on the surface of AZ31D prepared by high current pulsed electron beam was investigated.Grain boundary fuses on the modified layer and typical craters were observed on the surface of sample,by using OM and XRD analysis but the intermetallic phase Mg17Al12 was not observed.Gradient stress factors induce 120° fragments around the craters.Corrosion test of alloying layer shows that corrosion resistance improves with the increase of pulse times.