Incineration power generation is the main way to deal with domestic waste in China. The industry market is huge and the future development prospects are broad. For grate furnaces widely used in waste incineration power plants, there are problems such as high cost, long period, and non-detailed data results in model experiments and engineering experiments. Numerical simulation technology is usually considered for research work. Based on the combustion process and specific structure of waste in the grate furnace, the mathematical models of the gas-solid combustion process on the grate and the gas-phase combustion process in the furnace were described, respectively, and the existing modeling process of the grate furnace was summarized. The method of coupling calculations with different models to simulate the entire incineration process was highlighted. On the basis of expounding the modeling process of grate furnace, it focused on the content of numerical simulation research using Fluent software, and introduced the research and application of numerical simulation technology in grate furnace. At present, the relevant research mainly adopts the method of controlling variables to study the influence of a single parameter on the operation process of the grate furnace. Therefore, various parameters were classified according to fuel characteristics, operating parameters, structure of the grate furnace, and air and smoke system, and the progress and results of the research were analyzed and summarized. Based on the above analysis and research, the technical route of using numerical simulation technology to carry out design, construction and transformation and optimization of waste incineration power plants was proposed. Finally, the numerical simulation research of grate furnace was prospected to provide reference for further research work and practical engineering applications.