Additve manufacturing technologies are becoming increasingly widespread due to their advantages, as they enable the production of complex forms of products and in many cases the process is faster than conventional processes. They also reduce the cost of material waste. Aluminum alloys are increasingy replacing steel and other materials due to their mechanical properties as they have good strenght to weight ratio. In this diploma thesis the development of additive manufacturing of aluminium alloy AlSi5 with the MIG process is presented. This thesis is a study of welding parameters, which have the greatest influence on the quality of the manufactured walls and circle closed shapes. It also contain the research of influences of the first layer, the beginnings of weld and shifts on higher layer level. Result of this research is the final product, which is made with the most suitable welding parameters. This research confirms possibility of continuous additive manufacturing of aluminium alloy AlSi5 with MIG welding technology and also the selected optimal parameters. The influence of high thermal conductivity of AlSi5 for additive manufacturing was also proven and partial solutions to resolve this issue were tested.