Abstract: Research on the influence of urban building layout, such as building location and height, on the regional thermal environment distribution is of great theoretical as well as practical significance for rational urban planning and layout. In this paper, based on simulating microclimate characteristics in a region of the Dingshan District in the Nanjing Jiangbei New Area by using the ENVI-met model and different building layout elements as the design scene in one residential district, the influence of the ratio of the building height to the distance between buildings (H/W), and the building layout on the regional thermal environment is simulated and discussed. The temporal changes in simulated air temperature at the height of 2 m are found to be consistent with field observations. H/W and the building layout affect the regional thermal environment. To some degree, increasing H/W can reduce the air temperature in the summer, with the most comfort when H/W is 1.4. Larger air temperature differences are observed within various locations for various building layout conditions.