To investigate the impact of Heat-Air-Moisture Transfer (HAMT) in walls on the indoor thermal environment and energy consumption of pile-dwellings in northern Guangxi, this study establishes a model of a typical pile-dwelling using WUFI Plus software. The indoor temperature, humidity, and air-conditioning energy consumption are simulated and analyzed for both summer and winter under three scenarios: thermal, hygrothermal, and WDR. The results show that the hygrothermal model significantly enhances indoor environmental stability. In summer, it reduces the maximum temperatures in the living room and bedroom by 2.08 °C and 1.68 °C, respectively, and decreases the humidity fluctuation range by 19.1%–38.1% compared to the thermal model. In winter, humidity fluctuations are reduced by 29.7%–47.4%. This improvement leads to a reduction in summer cooling energy consumption by 4.3%–6.6%, although it increases the dehumidification load by 12.55%–35.2%. The influence of WDR is minimal (temperature reductions≤0.08 °C, humidity changes<0.2%, and fluctuations in cooling and dehumidification energy consumption<2%). These findings underscore the importance of incorporating HAMT into the thermal optimization and energy-efficient design of pile-dwellings to improve environmental comfort, reduce energy use, and guarantee simulation accuracy.