Hot cracking is one of the main problems involved in the casting of magnesium alloys and their joining by means of welding. Despite many research done, this type of cracking still constitutes a major problem in industrial practice. The present paper describes the impact of metallurgical, structural and technological factors on the susceptibility of the QE22 alloy to hot cracking of the repaired joints. A technology of repairing the QE22 alloy casts by means of welding and pad welding, was developed. The technology meets the qualification requirements according to EN 15614-4.