[Objective] The aim of the study was to make research on adsorption of Chinese walnut（Juglans mandshurica Maxim.） Shell（CWS） to Hg（Ⅱ） in water.[Method] Shells of Juglans mandshurica Maxim were used as biosorption to remove Hg（Ⅱ） in water solution to explore the influence to adsorption of Hg（Ⅱ） under different conditions,like pH solution,adsorption time,and Hg（Ⅱ）.[Result] The experimental results show that when absorptivity of Hg（Ⅱ） by CWS reached the highest,pH ranged within 5.0-6.0.The adsorptivity decreased as initial Hg（Ⅱ） concentrations increased.Fourier Transform Infrared Spectroscopy（FTIR） spectrum revealed some chemical groups of CWS may affect the adsorption of Hg（Ⅱ）,such as hydroxyl groups,methyl groups,aromatic methoxyl groups,unconjugated carbonyl,and typical aromatic ring,etc.Adsorption equation can be concluded considering the biosorption process relationship with Langmuir and Frendrich isotherm.[Conclusion] The study found that CW could be employed as a promising biosorption to remove Hg（Ⅱ） from aqueous environments.
