Bioconversion of lignocellulosic biomass into fermentable sugars using cellulase is indispensable for the production of biofuels and chemicals in the biorefining industry. However, the high cost and low efficiency of cellulase pose major obstacles to commercializing this process. In recent years, some significant efforts have been made to facilitate the application of cellulases in industry. Firstly, engineered Trichoderma reesei strains have been developed to enhance extracellular cellulase activities and efficiency. Secondly, the utilization of low-cost inducers and rational control of inducer feeding rates have facilitated economic production of cellulase. Finally, the development of sugar platforms with low cellulase dosage and high sugar concentration has enabled efficient lignocellulose conversion. These systematic efforts have collectively propelled lignocellulose biorefining toward a more economical and efficient industrial future.