Direct return of straw to the field will bring adverse effects on crop growth, and the addition of cellulose-degrading myxote in the process of returning to the field is an effective way to solve its adverse effects. Through plate preliminary screening, comprehensive determination of enzyme activity and straw degradation rate determination and re-screening, 5 high-efficiency cellulose-degrading bacteria were screened from decaying straw, cow manure compost, forest soil and other samples, among which X1 bacteria had the best enzyme activity and the most reasonable enzyme system composition, and their Cx, Cb, C1 and FPA reached 53.6 U/mL, 69.7 U/mL, 9.5 U/mL and 11.6 U/mL, respectively, and the degradation rate of straw reached 40.2%. A group of compound bacteria X1+X2 with significantly increased straw degradation rate were obtained, and the degradation rate reached 45.5%.According to the colony and individual morphological characteristics of X1 and X2, it was preliminarily determined that they were both Penicillium.