Abstract: In recent years, with the development of interdisciplinary researches in computer science with other disciplines, computational fluid dynamics numerical simulation has been widely used in the study of microclimate in urban environment. This has provided a new way for scholars to study the green space and achieve cooling effect more effectively in a limited area. This paper reviews the application of the cluster thermal time constant (CFD) numerical simulation method in researches on cooling and humidifying effect and outdoor thermal comfort evaluation of urban green space at multi-scales. On this basis, it summarizes the existing problems and shortcomings, and puts forward three prospects for future researches in the fields, in order to provide reference for future urban green space microclimate researches: 1) Extension study on multi-platforms and scales; 2) Comprehensive cross-analysis of microclimate characteristics; 3) Update of high-adaptation simulation models.