This paper considered the technology of electron beam welding with beam splitting. It assesses the possible application of the dynamic positioning of the electron beam in welding the aluminum alloy AlMg6. The beam is split into three and this is known as multipool welding. To study the effect of the split beam parameters on the geometric characteristics of welds, we performed a series of experiments with a three-level planning matrix. Using regression analysis, we obtained the dependences of weld depth, width, aspect ratios, and completeness of penetration on the main parameters of the welding process with splitting (the beam current, the welding speed, the beam exposure time at each point, and the distances between the points). We present an analysis of the obtained dependences. The criteria for characterizing the formation of defect-free welds are defined. We propose a method to determine the optimal modes of electron beam welding with splitting for aluminum alloys using monograms.