3D printer is a manufacturing method which builds layer upon layer and is in contrast to conventional manufacturing methods. This manufacturing method has the potential to significantly change the way of manufacturing and brings various advantages. In the past, since 3D printer was technically at an early stage, it was referred as Rapid Prototyping and was used only for prototype to confirm the shape. However, today, with technical enhancements, the usage is spreading from functional prototype, production tools such as jigs, to end use parts production. This paper includes case studies at Ricoh. Furthermore, this paper describes the possibility that 3D printer can change way of manufacturing and its limitations. The specific examples introduced in this paper focus on polymer.