Abstract: In recent years, some studies have shown that the influence of urban form on the thermal environment was more significant, but there were few studies that discussed it from the perspective of urban spatial structure. In order to evaluate the relative importance and mutual influence of urban morphological characteristics on surface temperature,this paper took the central area of Guangzhou as the research area, and selected the central 10 km area to divide it into basic units of different side length grids. The random forest regression model was used in different grids. Ten influencing factors were quantified on the grid scale, and the influence laws of water bodies, green spaces and buildings on the urban thermal environment were analyzed in depth. The results showed that the magnitude and direction of the impact of urban morphology indicators on surface temperature varied with seasons and observational scales. Building density, unit water area, unit vegetation area, and average building height were the 4 most important influencing factors, while factors such as sidewalk density and points of interest were less correlated with changes in surface temperature. Building form,water body and green space have dominant influences on surface temperature changes. Building density had an obvious positive effect on surface temperature, and the average height of buildings fluctuates with surface temperature. Urban green spaces and water bodies indicated a strong cooling effect, especially in summer.