The characteristics of nanometer material are presented in brief.Referring many domesticand overseas passages or sources , different processes, characteristics and progress of preparation are summarized. These processes include gas reacting process, precipitation process, micro-emulsion mediated process, sol-gel process, thermal process of solvent, solid reacting process, SPD process, liquid process in ultrasonicfield, supercritical fluid drying process ,self-assembled process. At present, uniform nanocrystals with an average particle size of about 5 nm can be obtained. Growth of crystals can be controlled to a certain extent in some oversea laboratory. Hence special size, special shape and special structurecan be obtained by selecting different method and preparation condition. In addition, developmental trend of preparation for nanometer is presented.