We performed field measurements and controlled field experiments to examine the flux, temporal variation and influencing factors of air–surface Hg(0) exchange at a high-altitude and remote site in the central Qinghai–Tibet Plateau. We found that the environmental conditions greatly influenced the air–surface Hg dynamics. Our results have important implications for the Hg biogeochemical cycle in the soils of Qinghai–Tibet Plateau under rapid climate warming and environmental change.