Additive manufacturing (AM) opens great opportunities for fabrication a wide range of products of almost any complex shape using minimum technological steps. However, with the development of additive technologies and implementation of various materials, research and engineering of materials became very important in this field. This is especially critical in fabrication of structural parts for essential components. One of the most critical products are the structures used in nuclear power engineering, in particular, the vessels and parts of nuclear reactors. The materials of these structures are subjected to serious requirements in terms of mechanical properties, both at room and high temperatures, high creep and corrosion resistance, as well as to requirements for low material activation in a high-energy neutron flux and low tendency to radiation swelling, which altogether should provide long-term safe operation of nuclear power plants. Oxide dispersion strengthened (ODS) reduced activation ferritic-martensitic (RAFM) steels quite well meet these requirements. Traditionally, such steels are produced by well-known powder metallurgy (PM) techniques. Despite the capabilities of PM to produce products of a rather complex shape, nevertheless, these capabilities are still limited, and the production of new-shaped parts requires the manufacture of new tooling, in particular, new dies. The wider potential of AM dictates the need to study the prospects for their application in obtaining such an essential class of materials. This book chapter analyzes and presents published developments on steels used in the nuclear power engineering, the requirements for them, the mechanisms of their strengthening, conventional methods for production; methods for synthesis of composite powders of ODS- steels as feedstock materials for AM, characteristics of composite powders synthesized by various methods; currently available experience in the use of laser-based additive technologies for manufacturing products from composite powders of ODS-steels. The review shows the prospects for the use of AM for the production of nuclear power plants parts from ODS-steels though there is still necessity for a large number of additional investigations in this direction.