The aim of the present work was to solve the technology for welding Mg alloy type AZ 63 with aluminium and to assess the quality of the fabricated joints (bimetals-composites). In solving the welding technology, the high affinity of Mg to oxygen has to be considered and therefore as suitable technology either metallurgical joining in vacuum (electron beam etc.) or high-speed solid state welding seem to be feasible. Explosion welding with Semtex S 30 explosive was approved experimentally. Parallel arrangement of welded materials was applied. The more plastic Al material was accelerated. Quality of bonds (bimetals) was assessed by defectoscopy (ultrasound), optical microscopy, microhardness measurement and X-ray microanalysis. It can be generally stated that the basic requirement on joint quality (namely the undulated boundary) was met. The structural composition and absence of inhomogeneities in fabricated bimetals suggest that the desired quality was achieved.