This chapter introduces the concept of biological solid waste, and evaluates the technical, social, economic, and environmental feasibility for management of different solid wastes. Solid waste can be sorted into various types. For example, on the basis of composition, solid waste can be divided into organic waste and inorganic waste; in terms of the form, it can be classified as solid waste, semisolid waste, liquid, and gaseous waste. Various kinds of technology such as landfill, anaerobic digestion, composting, thermal plasma technology, and incineration have been carried to manage the solid waste. Anaerobic digestion and composting are the major biological solid waste treatment methods all over the world. They could transform organic waste to bioenergy and compost. Macroscopically centralized and decentralized solid waste treatments are the major waste management patterns. Biological processing of solid waste has the advantages of simple operation, low cost, and high efficiency.