Eutectic high-entropy alloys (EHEA), also known as multi-principle component alloys (MPCA), are a group of materials exhibiting promising mechanical properties. The principle of the alloy is to achieve sufficient ductility due to the presence of the soft phase and, at the same time, increased strength due to the hard phase. In order for the newly discovered types of materials to be used commercially, it is necessary to verify their behaviour in technological operations such as welding processes. Therefore, the objective of the experiment was to evaluate the heterogeneous welded joint of the AlCoCrFeNi2.1 alloy with commercially used austenitic steel EN 1.4301 by electron beam welding. The parameters used during the process were previously verified on homogeneous joints. Subsequent observations were made by light and electron microscopy supplemented by chemical analysis. The mechanical properties of the formed joint were verified by a Vickers hardness test.