NOVELTY - A compound bacterium agent comprises Bacillus subtilis CICC10088 (108-1010), Bacillus cereus ACCC03002 (108-1010), Aspergillus niger CICC41130 (107-109), Aspergillus flavus CICC40258 (107-109), Trichoderma reesei CICC41491 (107-109), Trichoderma viride ACCC30150 (107-109), Sporotrichum thermophilic ACCC30346 (107-109) and Phanerochaetechrysosporium CICC40719 (107-109).    USE - For degrading crop straw of corn, wheat, paddy, sorghum grain and beans (claimed).    ADVANTAGE - The compound bacterium agent reduces rotten time of straws; improves the rotten efficiency; solves difficulty in transport and storage of straw; avoids air pollution caused by burning of straw; has good environmental benefits; produces metabolic product containing solid nitrogen and phosphorus that has good anti-insect effect, which is good for improving soil structure, crop yield and quality; and is prepared by simple, cost and low pollution method, and does not need large equipment.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of bacterium agent involving inoculating Bacillus subtilis CICC10088, Bacillus cereus ACCC03002, Aspergillus niger CICC41130, Aspergillus flavus CICC40258, Trichoderma reesei CICC41491, Trichoderma viride ACCC30150, Sporotrichum thermophilic ACCC30346 and Phanerochaetechrysosporium CICC40719 into medium, conducting culture, then inoculating into a solid medium, and conducting solid culture to obtaining solid bacterium agent A, B, C, D, E, F, G, and H, respectively; mixing the solid bacterium agent A (1-3 part by weight), the solid bacterium agent A (1-3 part by weight) the solid bacterium agent B (1-3 part by weight), the solid bacterium agent B (1-3 part by weight), the solid bacterium agent D (1-3 part by weight), the solid bacterium agent E (1-3 part by weight), the solid bacterium agent F (1-3 part by weight), the solid bacterium agent G (1-3 part by weight), the solid bacterium agent H (1-3 part by weight) to produce the compound microorganism bacterium agent.