My diploma project was to study the selective soldering processes and the optimization problems of selective soldering equipment. The thesis is dealing with the details of the formation and structure of the solderings. I reviewed the selective soldering technologies. I presented operating characteristics of the selective wave soldering machine which is used at the department of hybrid processes, while detailing the types of panels that are being processed there. I also showed the soldering defects of through hole-mounted components. I reviewed the steps of design experiments such as full factorial design, reducing the number of factors and I introduced its practical use. Selective soldering overview of the parameters have an affect on the soldering and as a result I have chosen the most influencing factors. After the optimization of the process I dealt with the measurement system in detail. Finally I applied the Microsoft Excel software and the Minitab 16 which is a statistical software that I used in order to determine the evaluation and the optimization of the process.