The substantial volume of archaeological sites necessitates significant energy consumption when employing air conditioning systems to provide fresh air to the display environment. Earth-air heat exchangers (EAHE) system, harnessing geothermal energy, exhibits considerable potential for energy savings within archaeological site exhibition facilities. This study established a coupled heat and moisture transfer model for EAHE, investigating the influence of three factors - outer pipe diameter, pipe length, and internal flow velocity - on the system’s outlet air temperature and absolute humidity. Furthermore, it analyzed the effectiveness and energy-saving potential of implementing EAHE system in a case exhibition hall in Nanjing. The findings indicate that: (1) Increasing pipe length and reducing airflow velocity enhance, the system’s effectiveness in summer cooling and dehumidification, as well as winter heating; (2) Continuous operation of the designed system for 10 h daily reduces annual fluctuations in outlet air temperature by 29.97 ℃ and absolute humidity by 0.0057 kg/kg; (3) Application of the system in the case exhibition hall results in an annual cooling and heating capacity of 49.3 MW. This research provides a viable solution for the sustainable conservation of archaeological heritage.