Abstract:The effect of initial solution pH values, biomass doses, and initial ion concentrations on the removal efficiency of Ni(II) by fruiting body of Auricularia polytricha was studied using the Response Surface Methodology (RSM). The biosorption of Ni(II) by fruiting body of A. polytricha was carried out with batch experiments and the optimal experimental condition was determined using the central composite design(CCD). Results showed that the Ni(II) biosorption processes were affected significantly by pH values, biomass doses, and initial ion concentrations (P<0.0001). The optimum parameters of the biosorption of Ni(II) were found to be 5.41, 6.00g/L and 24.0mg/L for initial pH, biomass dose, and initial ion concentration, respectively. At the optimal conditions, the biosorption efficiencies of Ni(II) by A. polytricha were 87%. The value of R2(0.9771) indicates a high correlation between the observed and the predicted values.