Nano-ceramic refers to ceramic material whose grain boundary width, grain size, defect size and second-phase distribution are all on nanometer scale. Overcoming traditional fatal short comings of ceramic-brittleness, and performing a great role in many aspects including superplasticity, ferroelectric properties and mechanical properties, it has aroused wide concern. Preparation methods of nanometer ceramic powder including physical synthesis and chemical synthesis were reviewed. Since the physical synthesis method consumed a large amount of energy and required a large investment in equipment, powder preparation method was mainly adopted to prepare nanometer ceramic powder. In the late period of powder preparation, dispersants and ultrasound were applied to resolve its agglomeration. Molding and sintering process directly affected the performance of nano ceramic. The molding process included dry and wet process. Dry molding was simple and feasible, and molded samples were homogeneous, but it might introduce impurities easily; wet molding could minimize impurities and agglomeration, but the process was complicated and harsh. The sintering method was divided into pressureless sintering and pressure sintering. During the sintering process, various technicals were faced with the difficulty of limiting the particles in the nano-level. Finally, the mechanical properties, ferroelectric properties and superplasticity of nano ceramic were elaborated, and its application and innovation in the fields of protection and coating, biomedical materials and utensils were briefly introduced.