The West China Rain Zone (WCRZ), one of worldwide biodiversity hotspots, is vulnerable to pollutant exposure. Mercury (Hg), as a global toxic pollutant, could enter into this ecosystem by wet and dry deposition, potentially posing ecological risks. Therefore, it is essential to investigate the patterns, controlling factors, and source contributions of Hg deposition in this region. This study presents a three-year comprehensive analysis of atmospheric Hg wet deposition at Mt. Emei of this biodiversity hotspot region. Results revealed the elevated Hg concentrations with volume-weighted mean concentration (VWMC) of 15.6 ± 9.8 ng L