Bioethanol is a kind of  flammability alcohol that is made by fermenting plants. It is suitable for use as fuel for internal combustion engines such as automobiles. It is a bioethanol which is used for the improvement of atmospheric environment, energy security and global warming. It is emerging as an effective solution. There are only about 10 kinds of crops that are used as raw materials worldwide based on economical efficiency and technical ease. Among them, corn, barley, wheat, rice, cassava, potato, and sweet potato are representative crops using plant-containing starch. Molasses and sugarcane are examples of sugar crops. This article looks at the bio-ethanol industry in the US and Brazil.