A total of twenty-four isolates of actinobacteria from arsenopyrite, pyrite, polymetallic sulfides and magnetite from Peruvian mining zones have been used with the purpose of characterizing them by morphological, physiological and molecular studies for future biotechnological applications. 23 strains were identified as Streptomyces and1 as Actinomadura sp.95% and 70% of the strains were able to grow at pH 3.5 and pH 2, respectively. Only 19% of them were able to oxidize iron at pH 2. Also, they have been tested by growth on arsenopyrite tailings and Streptomyces sp. E1 and Streptomycesvariabilis AB5 leached 19.1 % and 15.5 % of arsenic, respectively, while the control without inoculum only showed 2.5% of leaching. Results indicate that these strains show important characteristics for leaching processes.