Abstract: High cellulase-producing strains of microorganisms were screened and identified from soil at mulberry fields. Using CMC-Na as the sole carbon source, 12 target bacteria were isolated with Congo red dyeing. YZB46 was found to show the greatest cellulasesecretion among all. Preliminary analysis on thesecreted metabolitesindicated that the endo-cellulaseactivityreached 17.08 U·mL^-1 at pH 6.0 and 40 ℃, and the enzymedisplayed a desirable genetic stability. Based on the results of morphological observation, gram-staining, physiological and biochemical characterizations, as well as 16S rDNA sequencing, the isolated YZB46 appeared to beclosely related to Bacillus cereus.