A gene encoding an endo-β-1,4-glucanase,which was isolated from Aspergillus niger DL08 by using an RT-PCR protocol and its nucleotide sequence was determined. The eg1 cDNA contained a 999 bp open reading frame encoding a 332 amino acid protein with an estimated molecular mass of 36. 75 kDa and isoelectronic point( pI)of 4. 38,named eg1. Based on domain analysis presumed the eg1 contains 18 amino acids signal peptide,a catalytic domain of glycosyl hydrolase family 5( GH5) C-terminal catalytic region. The recombinant endo-β-1,4-glucanse eg1was purified by Ni-affinity chromatography from the intracellular fraction of Escherichia coli. The optimal activity of the purified enzyme was displayed at a temperature of 45 ℃ and pH 5. 0 when sodium carboxymethyl cellulose was used as a substrate,respectively. The end products of the hydrolysis of 1% sodium carboxymethyl cellulose by eg1 were detected by thin layer chromatography,mainly continuously oligosaccharides. These properties would provide technical parameters for utilizing cellulose for the production of biochemicals and renewable biofuels.