Municipal sludge is a by-product in the sewage treatment process, and its main properties include high moisture content, containing organic toxic substances, large specific surface area and porosity, and easy to produce irritating gases. Biomass is a renewable energy source, including wood, straw, rice husks, sawdust, etc. This article mainly takes garden waste as an example. The co-pyrolysis of municipal sludge and garden waste is of practical significance for the reduction and resource utilization of both. This article summarizes the development and application of co-pyrolysis of municipal sludge and garden waste.