The Water Defense River and Lake Composite Microbial Deodorizer is a novel bio-deodorization and purification agent, formulated following the principles of microecological engineering. It is developed by integrating advanced composite microbial technology from abroad, utilizing microecological engineering techniques. This product is made by carefully selecting a variety of beneficial microbes through a composite fermentation process. It effectively eliminates multiple malodorous gases, achieving a deodorization and fly suppression rate of over 70%; it significantly reduces the COD and ammonia nitrogen content in wastewater, enhancing the purification speed and capability of wastewater. It is non-toxic and non-side effect to humans and animals, and does not produce any pollution to the environment.