The invention relates to 
microbial agent and the preparation method and usage thereof, which belongs to the preparation method and the usage of 
bacteria agent. The 
microbial agent solves the problems that the 
fermentation time of the organic wad material is long, the 
fermentation process is complicated, the 
bacteria quantity is not easy to be controlled and determined, and the 
bacteria is easy contaminated by other bacteria in the prior ecological pig raising method. The 
microbial agent is made through mixing 
lactic acid bacteria, microzyme, 
photosynthetic bacteria, actinomyceto and filamentous fungi. The microbial agent adopts that the 
lactic acid bacteria, the microzyme, the 
photosynthetic bacteria, the actinomyceto and the filamentous fungi are mixed, wherein the 
lactic acid bacteria, the microzyme, the 
photosynthetic bacteria, the actinomyceto and the filamentous fungi are cultured through first-stage slant culture, second-stage liquid seed culture and third-stage liquid 
fermentation culture. The 
degradation process can be completed in seven to ten days by the microbial agent provided by the invention, the 
maximum temperature in the process can reach 60 to 65 DEG C, the bacteria quantity is fixed, the method is simple, and the microbial agent has no environmental 
pollution.