Six strains having good ability of degrading the cellulose were prepared by screening from soil and rotted straw,then,the PFA enzyme activity and CMC enzyme activity of the six strains were determined.The results showed that X-3,X-4,X-5 had the maximum activity,the FPA and CMC of X-3 were 2.69 U/ml and 33.28%,the FPA and CMC of X-4 were 24.70 U/ml and 60.55 U/ml,the FPA and CMC of X-5 were 9.06U/ml and 44.91U/ml.The degradation rate of the straw of X-3,X-4,X-5 in 7days were 39.35%,44.38% and 52.40%.According to characters of colony and single bacteria,it was preliminary determined that X-3 and X-5 belong to Trichoderma koningii.