An object is to identify endoglucanase and β-glucosidase genes by isolating genomic DNA containing cellulase genes, which are classified into endoglucanases or β-glucosidases, from Acremonium cellulolyticus, and sequencing the nucleotide sequences thereof. The inventors intensively compared the amino acid sequences of known endoglucanases and β-glucosidases with each other to find conserved region of amino acid sequences in Acremonium cellulolyticus, and various primers were designed based on the information. PCR was carried out using the various primers thus designed and genomic DNA or cDNA as a template. As a result, gene fragments of endoglucanases and β-glucosidases were obtained. Primers were designed based on the gene fragments, and PCR was carried out to amplify nine genes of endoglucanases and β-glucosidases. The nucleotide sequences thereof were sequenced, and the present invention was completed.