Abstract: Harmful gas released from the fermented slurry during storage, water pollution caused by the fermented slurry discharged directly, heavy metal enrichment and groundwater pollution caused by overuse fermented slurry as fertilizer for a long time were the adverse effect of straw anaerobic fermentation project on the environment. Improving the fermented slurry tank to reduce and adsorb the harmful gas, constructing the equipment to decontaminate the excrescent fermented slurry, appyling fermented slurry as fertilizer with scientific guidance, and developing the new production from fermented slurry were important ways to avoid the adverse effect and promote straw anaerobic fermentation project evolution.