Now, lots of efforts are underway to determine the type of pretreatment more efficient for lignocellulosic materials but which method is suitable is not yet clear. However, irrespective of pretreatment technology, for reducing the energy costs of the process, a low solid-liquid ratio (S/L) and mild temperatures in the pretreatment are important, thus economizing both steam and electricity. Although various studies were carried out on S/L ratio limited studies have been done on the corncob with combination of acid and alkali treatment.