Under the tendency of microminiaturization of 3C products,there are strong needs to the metal foil with high quality in the field of electron,computer,medical treatment,energy and traffic. It makes research and development of foil rolling became a new hotspot. It is discussed to the research, production and application of various metal foils. The foil mills and their products in the world are introduced. The minimum thickness of foil by asymmetrical rolling is discussed and a new formula is proposed in which the rate of across share zone is taking into account. The three important new discoveries in the foil rolling are introduced,that is,the extreme extensibility,the atypical plasticity,and the deformation induced reaction diffusion. The reason is analyzed from the viewpoint of size effects. The phenomena of single layer crystal grain,work softening and size effects found in the experiment are discussed. Some special factors are proposed,so as to explain the mechanism of foil rolling. The application of crystal plastic finite element method in foil rolling is introduced,and the next development in foil rolling is also pointed out.