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The aim of the present work is to assess the compatibility of Sarcheshmeh molybdenite concentrate with native bacteria of the area. The strain of thiobacillus ferrooxidans was isolated from Sarcheshmeh mine drainage and the test work were performed in shake flasks. Effect of increasing pulp density from 1 to 5%, changing the culture medium from 9K to Norris and addition of surfactant Tween 80 on the performance of the bioleaching was investigated. The results were compared to the chemical leaching process. It was revealed that Mo dissolution in bioleaching of molybdenite was 6 times greater than chemical leaching. It was also found that thiobacillus ferrooxidans was able to leach pyrite and copper sufide at higher rate compared to molybdenite, and consequently reduced the Fe and Cu content of molybdenite concentrate. Application of Norris culture medium or addition of Tween 80 to 9K medium for dissolution of Cu and Fe content of molybdenite can reduce the time of bioleaching and its process cost.