Bioleaching/biooxidation processes have been commercially applied for the recovery of copper, gold and uranium for two decades. Concerning these processes by mesophiles and thermophiles, academic and commercial applications have been extensively increasing in laboratory, pilot, full scale operations. Several bacterial species are used in many commercial operations in South America, Australia, South Africa, India, China. In near future Turkish copper and gold mines will probably use these processes as commercial applications due to the economical and environmental reasons. Therefore, the close relationship between biooxidation and cyanidation with mineralogical composition is important for the commercial selection of these processes. In addition to lab tests, full-scale feasibility studies being performed to determine the impacts of climate and environmental factors for potential mining areas will also be completed in the near future. This paper presents an investigation of the potential bioleaching developments in Turkey. (C) 2003 Elsevier Ltd. All rights reserved.