In order to screen high-efficiency lignin-degrading bacteria, effectively improve the degradation efficiency of agricultural straw. In this experiment, samples were collected from the broad-leaved forest soil in Changbai Mountain, and strains were isolated and screened through the method of aniline blue-differentiation medium primary screening and enzyme activity re-screening. The screened high-efficiency target strains were identified for 16S rRNA strains. In order to improve the enzyme production of the strains Performance, select carbon source, nitrogen source and initial pH, culture temperature, inoculation amount and time, etc. We use orthogonal test to optimize enzyme production conditions, and then conduct straw solid state fermentation test to verify its degradation ability.The results show that the strain DT-2 obtained by the re-screening has high enzyme activity and can be used as the target strain for the next test, it was identified as Bacillus subtilis. The results of the enzyme production optimization test showed that when the strain DT-2 uses lignin as the only carbon source and urea as the only nitrogen source,the initial pH value is 6, the cultivation temperature is 37 ℃, the inoculum amount is 5%, and the cultivation time is 30 h. The activity has the optimal value, in which Lip enzyme activity is 38.44 U/mL, Lac enzyme activity is 26.78U/mL, Mnp enzyme activity is 35.56 U/mL. The results of the solid-state fermentation test showed that the straw weight loss rate in the control group was 2.1%, and the straw weight loss rate in the test group was 13.5%, and the degradation efficiency was increased by more than 20 times. In summary, the strain DT-2 isolated in this study has high lignin-degrading enzyme activity, can effectively improve the efficiency of straw degradation, and has a good application prospect in the harmless treatment of agricultural straw.