The Gram-negative, facultative anaerobic strain, LZ-5 producing alkaline cellulase had been screened and isolated from the alkaline soil of paper mill. The strain was identified to be a kind of genus Vibrio. The cellulase activity of culture liquid was 5.8 U/mL.The primary study on enzymatic properties showed: optimum temperature of 40℃, optimum pH of 9.0, with stable enzymatic activity under alkaline condition. The strain LZ-5 was tested by the experiments of subculture and the results showed that the strain LZ-5 had genetic stability.