The main aim of this study is to summarize the steps of operation of an automatic milking system. The milking system is used in a fresh milk producing farm: the Józsefmajor Experimental and Demonstration Farm of the Szent István University of Gödöllő. The use of automatic milking robot system is unique in Hungary and also in Europe. The installation of the milking robot changed the steps of the formerly installed HACCP system and made the milking process more simple: due to the fully automatic milking process there are less physical and biological critical points. In summary, automatic milking system helps to harmonize the milking, feeding and relaxing period of the herd, and also makes the compliance with food safety regulations easier. The second aim of this study to define the possible cost-benefit changes due to the automatic milking system in the dairy farm. Further aim of this study to shows economic methods which help the farmers to make decision about milking systems.