Iron-oxidizing bacteria (IOB) which get energy through the oxidation of ferrous are widely found in environments.1OB have played important roles not only in bioleaehing (biooxidation) of minerals but also in the desulfurization of coal and gases containing hydrogen sulfide or sulfur dioxide.Both processes imply the chemical oxidation of sulfide by ferric iron; the resultant ferrous iron is re-oxidized to the ferric state by microbes.Therefore, the high ferrous biooxidation rate and large volumes of ferric iron solutions are necessary in all above mentioned cases.It has been reported that many microorganisms are capable of oxidizing ferrous iron; and the bioleaching (biooxidation) and biodesulfurization with pure culture has also been investigated.Naturally, ferrous iron oxidation and mineral bioleaehing are occurred with the cooperation of many microorganisms.It has been proposed that the consortium that can oxidize efficiently ferrous iron or/and minerals in a short period of time.