In this final Bachelor's thesis, "Design of 3D-Printer" provides advanced design model of SLS 3D-Printer after reviewing several existing printers. Some of them were compared with overall designs. New technology of twin laser system is introduced. Advanced analysis and calculation for Sintering process and necessary calculations for drive components has derived. CAD model of the entire printer is designed with some unique features. Strength calculation has been made and electrical control scheme has been designed. Physical properties of the material that are to be sintered is analyzed (Nylon PA-12). Requirements of the laser system have been shown.