Nanotechnology provides a new method on modified cement. It introduces the research and application of nano cement situation and existing problems in the paper. The nano cement has better mechanical properties and durability than the current ordinary cement, and it is environmentally friendly. It can improve the microstructure of cement in order to improve their physical and mechanical properties and durability, and it can reduce energy consumption. The current focus is to study the microstructure and mechanical properties of nano concrete, as well as how to prepare inexpensive nanomaterials. Future, the nano cement will have a wider application field.