The aim of the present paper was to determine the role of Fe-oxidizing bacteria in trace metal solubilization during sphalerite oxidation. For this purpose, a trace element bearing sphalerite mineral was used in the oxidation/leaching experiments (biotic & abiotic). The experiments were conducted biologically and abiotically under aerobic conditions at pH 3. Acidithiobacillus ferrooxidans was used in the biological sphalerite oxidation experiments. The results showed that bacteria play the major role in the release of trace metals from sphalerite by enhancing the oxidation kinetics. These results indicate that in order to develop proper rehabilitation strategies for Acid mine drainage systems the role of bacteria should be determined.