Abstract: Experimental investigations on the electron beam welding of aluminum alloy 2A14 are presented in this paper. Experiments are carried out to study the influence of welding parameters, such as beam current, welding speed, focal location, scanning graph, graph size and scanning frequency, on the penetration depth and width of welds based on an orthogonal test and analysis method. The results showed beam current and focal location had the greatest effect on penetration depth and width of welds, welding speed was next, and beam scanning parameters, such as figures, size and frequency, relatively affected much less. The joints welded by the optimum parameters are good appearance and quality. The microstructure of weld zone is composed of α phase and eutectic structure grains.