This Brief highlights different approaches used to create stable cellulase and its use in different fields. Cellulase is an industrial enzyme with a broad range of significant applications in biofuel production and cellulosic waste management. Cellulase 7a from Trichoderma reesei is the most efficient enzyme in the bio hydrolysis of cellulose. In order to improve its thermal stability, it can be engineered using a variety of approaches, such as hydrophobic interactions, aromatic interactions, hydrogen bonds, ion pairs and disulfide bridge creation.