The adsorption of heavy metals on bacteria is often employed in the remediation of various contaminations. Nevertheless, the difference in the adsorption behaviors of the bacteria of different growth stages has not yet been systematically studied. Based on the adsorption experiments of Cu2+on Acidothiobacillus ferrooxidans at different growth stages, it is found that the adsorption capacity of the bacteria at the logarithmic stage is slightly higher than that of the stationary stage. The adsorption on the bacteria at the logarithmic stage and at the stationary stage can be described by Freundlich equations, implying its high surface heterogeneity. In addition, a negative correlation between the adsorption amount of bacteria and the pH of solution can be observed. Therefore, the displacement reaction between Cu2+ and surface proton of the bacteria may constitute the adsorption mechanism. The changes in surface chemistry of the bacteria at different growth stages are considered to be responsible for the difference in adsorption behaviors.