Ecological method and system for treating excrement

The invention relates to an ecological method for treating excrement. The method comprises the step of performing solid-liquid separation on the excrement to obtain waste liquid and solid waste, wherein the waste liquid is used for planting pennisetum hydridum or pennisetum purpureum after being treated by the compound microorganism preparation, and the solid waste is used for culturing the earthworms or fly maggots; the planted pennisetum hydridum or pennisetum purpureum is used for livestock or fish culture; the compound microorganism preparation is mainly prepared from 70%-80% of rhodobacter capsulatus, 5%-20% of spherical bacteria and 5%-15% of pseudomonas gelatinasa. By use of the ecologic method disclosed by the invention, the pollution on the surrounding environment by the culture industry is relieved, and the quality security of the cultured aquatic product is guaranteed at the same time; the waste liquid is treated by adding the specific microorganism preparation, the existent odor is removed, the ai