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Knockout of the transcriptional repressor <i>Trctf1</i> is known to enhance the yield of cellulose-induced cellulase synthesis in <i>Trichoderma reesei</i>. However, different inducers possess distinct induction mechanisms, and the effect of <i>Trctf1</i> on cellulase synthesis with soluble inducers remains unknown. To evaluate the effect of the <i>Trctf1</i> gene on cellulase synthesis and develop a high-yielding cellulase strain, we established a CRISPR–Cas9 genome editing system in <i>T. reesei</i> Rut C30 using codon-optimized Cas9 protein and in vitro transcribed RNA. This study demonstrated that <i>T. reesei</i> ΔTrctf1 with the <i>Trctf1</i> gene knocked out showed no statistically significant differences in cellulase, cellobiohydrolase, endoglucanase, and β−glucosidase production when induced with MGD (the mixture of glucose and sophorose). However, when induced with lactose, the activities of these enzymes increased by 20.2%, 12.4%, and 12.9%, respectively, with no statistically significant differences in β−glucosidase activity. The hydrolysis efficiency on corn stover of cellulases produced by <i>T. reesei</i> ΔTrctf1 under different inducers was not significantly different from that of wild-type cellulases, indicating that <i>Trctf1</i> gene deletion has little effect on the cellulase cocktail. These findings contribute to a better understanding of the molecular mechanisms underlying the regulation of <i>T. reesei</i> cellulase synthesis by different soluble inducers, as well as the construction of high-yield cellulase gene−engineered strains.