Abstract: A strain bacteria had been separated,purified from the removal of manganese bio-filter treated with groundwater by traditional microbiology method.The strain bacteria could oxidate Mn²⁺ tested by the LBB method.It had been identified to belong to Rhodococcus sp.by the MIDI Sherlock bacteria identification system.Studied on the capacity and induction of Rhodococcus sp-1 biological manganese removal,the results shown: the removal amount of Mn²⁺ was 35mg/L when Rhodococcus sp-1 reached the first stabilization period,and it's order was 2.3×10⁸n/mL.It had the strong capacity of biological Mn²⁺ removal.In addition Fe element could induct Rhodococcus sp-1 to oxidize Mn²⁺.Under the same conditions,Fe³⁺ was stronger than Fe²⁺,the induction speed ratio was 3~4∶1;organic Fe³⁺ was stronger than inorganic Fe³⁺,the induction speed ratio was 1.6~2∶1.