Through the screening experiment and the cellulase activity measurement experiment,eight cold-adapted cellulose-decomposing bacteria have been isolated from forest humus at Heilongjiang Province for increasing the resources of cold-adapted cellulose-decomposing bacteria for composting.Among the eight bacteria,the strain B6-15 had the highest cellulase activity of 24.94 U/mL.And when the strain B6-15 was cultivated at pH 7.0,0.25% of NaCl concentration,it could get the maximum growth.Strain B6-15 was identified as a Pseudomonas sp.by its morphological,the physiological and biochemical properties and 16S rDNA sequence analysis methods.Then the thermal stability of cellulase produced by strain B6-15 was examined and the result showed that the cellulase was a kind of cold active enzyme and had 54.43% residual activity at 10℃.