The interior spaces of large-span site museums can typically be categorized into relic preservation areas, visitor corridors, and non-occupied spaces, with only the relic preservation areas and visitor corridors requiring environmental control. The conflicting needs of visitors and relics often render inefficiencies in simultaneously satisfying the thermal needs when using a sole environmental control system. To address this, an independent local environment control method that employs an air curtain to isolate the visitor corridor from the unoccupied space, along with displacement ventilation (DV) systems to regulate the local environment for the visitor corridor and relics, is proposed in this study. The effects of the supply air inlet and air curtain on the performance of the DV system and the feasibility of an independent local environmental control system were evaluated. The results indicated that the performance of the DV system in the visitor corridor was optimal when the height of the air inlet was 0.6 m. When both DV systems were operating, the mean temperature and relative humidity (RH) were 25.6 °C and 68.6 %, respectively, in the visitor corridor, and 20.6 °C and 95.3 %, respectively, in the relic preservation area; both visitor and relic requirements were met independently. This study provides a newly designed independent local environmental control system for museums.