Abstract: The conversion of lignocellulose into fuel ethanol is one of the ways to ease the energy and environmental crisis. To reduce the production cost of converting lignocellulose into biofuel, it is necessary to increase cellulase production or to screen cellulase with higher enzyme activity. Genus Novosphingobium belongs to Sphingomonads. The metabolism of the bacteria in this family is diverse, which can degrade organic compounds and also can be used for lignin degradation. However, the research on cellulase gene of Novosphingobium has not been reported. In this study, we cloned and expressed the cellulase gene Nspcel8 A of a Novosphingobium strain 9-1 with high cellulase activity and identified its enzyme characteristics. Nspcel8 A contains a catalytic domain belonging to glycoside hydrolase family 8（GH8）. The enzyme achieved heterologous expression in Escherichia coli and obtained an expression product. The optimal pH and temperature of Nspcel8 A for carboxymethyl-cellulose（CMC）were 4.0 and 40 ℃, respectively. Nspcel8 A had good pH stability and can maintain above 60% activity after incubation at the pH range of 3.5～11.0 for 24 hours. The Kmvalue of Nspcel8 A to CMC was 10 mg/mL and Vmaxwas14 μmol·min-1·mg-1. The substrate specificity test showed that NspcCel8 A had the highest enzyme activity（8.40 U/mg） for CMC, but had low or no enzyme activity for insoluble cellulose PASC and Avicel. High-performance liquid chromatography analysis of the hydrolysis products of Nspcel8 A against cello-oligosaccharides showed that Nspcel8 A can’t degrade cellobiose, cellotriose and cellotetraose, it can partially hydrolyze cellopentose into cellobiose and cellotriose, and degrade cellohexaose into cellobiose, cellotriose, and cellotetraose. The above results showed that Nspcel8 A was an endoglucanase, which can not hydrolyze crystalline cellulose, indicating that Nspcel8 A was not the main cellulose degrading enzyme of Novosphingobium sp.9-1.