<p>During Antarctic region drilling, the interaction between the drilling fluid and ice layer constitutes a critical factor influencing drilling safety and efficiency. This study investigates in depth the adsorption-heat transfer mechanism between drilling fluid (butyl acetate) and ice layer, as well as their implications for wellbore stability in the Antarctic region. To this end, a fully coupled model integrating adsorption mass transfer, fluid-solid heat transfer, and solid mechanics is developed. First, the relevant physical parameters of butyl acetate are measured experimentally. As the temperature decreases from 5°C to −55°C, the density of butyl acetate varies from 0.88 to 0.96 g cm⁻³, the viscosity increases from 0.933 to 3.327 mPa s, the thermal conductivity rises from 0.140 to 0.157 W m⁻¹ K⁻¹; the enthalpy change associated with the adsorption of butyl acetate on the ice surface is 8.84 kJ mol⁻¹. Then, numerical simulations of the model reveal that the heat exchange between the drilling fluid and ice layer causes an increase in the temperature of the ice layer near the wellbore, which significantly alters the physico-mechanical properties of the ice layer and increases the risk of wellbore instability. Meanwhile, the adsorption of drilling fluid on the well wall proceeds as a dynamic equilibrium process that absorbs part of the heat, thereby mitigating the thermal impact and offering limited short-term protection to the wellbore. However, continued heat transfer ultimately reduces wellbore stability over time. The model is validated using a drilling case from the Antarctic Dome A area, achieving a 99% match with literature-reported failure depths. The critical wellbore failure depth decreases from 1649.02 to 1632.12 m when adsorption and heat transfer effects are accounted for. These findings provide a theoretical foundation and technical guidance for enhancing drilling safety and efficiency in the Antarctic region.</p>