Abstract: In recent years, livestock and poultry industry has developed vigorously, with amount of poultry waste generated by livestock and poultry farms increasing annually．It has caused significant pollution and ecological deterioration in surrounding soil and water environment．China has introduced a series of policies to encourage livestock and poultry breeding waste comprehensive utilization．Composting and fermentation in biological fermenters are effective methods for treating livestock and poultry manure．To addresses challenges of treating livestock and poultry manure, a horizontal equipment for harmless treatment was designed and developed, to conduct harmless fermentation experiments．Designed harmless treatment equipment mainly included a feed and outlet system, a fermentation drum, an electric heating system, and an aeration system, with a total power of 39 kW and a high automation degree．Different fermentation processes could be configured to treat livestock and poultry manure based on different raw materials and bacteria strains．Cow manure fermentation experiment result showed that the maximum fermentation temperature reached 70 °C, with a total processing time of 18 days．Material underwent complete fermentation, with moisture content reduced to 61%．Fermented material appeared as a black brown powder．Fermentation experiment was excellent．Treated material exhibited a high degree of decomposition and safety．It could be used as a primary organic fertilizer or undergo further processing to become a commercial organic fertilizer．