Abstract: By investigating the adsorption properties of manganese on major mineralized components of the surface sediment in a reservoir, the migration and transformation mechanisms of manganese across the sediment-water interface can be more clearly explained. The surface sediment of Wangjuan Reservoir was taken as an example, and a chemical selective extraction method was used to separate the mineralized components, including Fe oxides, Mn oxides, organic matter, and clay minerals from the sediment. Subsequently, the adsorption characteristics of Mn(Ⅱ) on the components as well as their contributions to Mn(Ⅱ) adsorption were investigated. The results showed that the contents of extracted organic matter, Fe oxides and Mn oxides of the surface sediment were 16.23,10.12 and 1.771 mg/g, respectively. Both Langmuir and Freundlich isotherms can be applied to well describe the Mn(Ⅱ) adsorption process on the surface sediment and major mineralized components. Compared with Freundlich isotherm, the Langmuir isotherm better represented the effects for the experimental data with correlation coefficients above 0.95. The adsorption quantities of Mn(Ⅱ) on Mn oxides, Fe oxides, organic matter and clay minerals were 77,2.5,38,4.0,17,4.5 and 44.0 mg/g, respectively. Considering the significant difference of component contents in the surface sediment, the contribution of organic matter and Fe oxides were 2.24 and 1.91 mg/g, which were obviously larger than those of clay minerals (1.22 mg/g) and Mn oxides (0.62 mg/g).