The paper provides a brief review of bioethanol, a valuable energy source. Various problems like the depleting fossil fuel resources, environmental related problems such as greenhouse gases have sprung forth the awareness of the value of renewable and cleaner sources of energy, such as bioethanol which is produced from lignocellulosic biomass. It is a valuable, biodegraded and transportable biological fuel. So, bioethanol production from lignocellulosic material holds tremendous potential in terms of meeting energy needs and providing various environmental benefits. The review has discussed about the lignocellulosic material, its composition, its pretreatments such as physical, chemical and biological pretreatments, the enzymes and the hydrolysis reaction and composition analysis including some benefits of ethanol as a biofuel.