Underground spaces offer significant potential for sustainable urban development, particularly in cold climate regions where surface thermal fluctuations are extreme. However, optimizing the wind–heat environmental performance of such spaces remains insufficiently explored, especially in relation to spatial morphology. This study addresses this gap by investigating how underground spatial configurations influence thermal comfort and ventilation efficiency. Six representative spatial prototypes—fully enclosed, single-side open, double-side open, central atrium, wind tower, and earth kiln—were constructed based on common underground design typologies. Computational fluid dynamics (CFD) simulations were conducted to evaluate airflow patterns and thermal responses under winter and summer conditions, incorporating relevant geotechnical properties into the boundary setup. The results indicate that deeper burial depths enhance thermal stability, while central atrium and wind tower prototypes offer the most balanced performance in both ventilation and heat regulation. These findings provide valuable design guidance for climate-responsive underground developments and contribute to the interdisciplinary integration of building physics, spatial design, and geotechnical engineering.

This paper firstly defines the concepts of underground atrium body shape, climate adaptability and parametric design, analyses the climatic characteristics of cold regions to extract their climatic factors, and responds to the climate with the light and heat environment, extracts the influence factors of the light and heat environment of the underground atrium and the body shape factors of the underground atrium, and constructs the underground atrium body shape design parameter system according to the classification of the body shape factors. Secondly using Ladybug+Honeybee software, a parametric underground atrium performance simulation system is con-structed to simulate the light and heat performance of the underground atrium under the non-air-conditioned state by controlling the design parameters of the underground atrium's body shape, and to explore the role of each body shape parameter in relation to the light and heat environment of the underground atrium respectively. Then, using Ladybug+Honeybee+Wallacei software, we construct a multi-objective optimisation system for under-ground atrium shapes under non-air-conditioned condition with differentiation of light and heat performance, and explore underground atrium shapes suitable for cold regions.