This research was carried out to estimate the removal of Cd2+ from an aqueous solution by pretreatment of Humicola sp. biomass with acid (H2SO4) and base (NaOH). The influence of different treatments of dried Humicola sp. biomass on its Cd2+ biosorption activity, indicated that 10% NaOH was increased biosorption of Cd2+ in comparison with the untreated and acid treated biomasses. Maximum Cd2+ biosorption of pretreated biomass by base took place at initial solution at pH 6 and 7 after 150 minutes, while the maximum adsorption of Cd2+ in pretreated biomass by acid was obtained highest at pH 6 after 60 minutes. Cadmium ions removal increase within the temperature has raised more than 40 oC. Desorption experiments indicate that the desorption efficiency with 0.1 M HNO3 solution reaches 96.35% and 83.32% in acid and base treatment, respectively.