The biogeochemical cycling of manganese is recognized as an important environmental process because manganese is not only an essential nutrient for all organisms but also its oxidation and reduction are intimately coupled with the cycling of other essential elements. Studies have demonstrated that Mn2+-oxidizing bacteria are abundant and distributed widely. A diverse array of bacteria, fungi, and microalgae have been shown to have the ability to catalyze oxidation or reduction of manganese. The oxidation of soluble Mn2+ to insoluble Mn3+/Mn4+ oxides and oxy-hydroxides is an environmentally important process because the solid-phase products oxidize a variety of organic and inorganic compounds, scavenge many metals, and serve as electron acceptors for anaerobic respiration. In most environments, Mn2+ oxidation is believed to be bacterially mediated. Over the years, Mn2+-oxidizing bacteria have been isolated from wide variety of environments, including marine and freshwaters, soils, sediments, water pipes, Mn nodules, and hydrothermal vents. Phylogenetically, Mn2+-oxidizing bacteria appear to be quite diverse, with all isolates analyzed to date falling within either the low G+C gram-positive bacteria, the Actinobacteria, or the α, β, and γ subgroups of the Proteobacteria branch of the domain Bacteria. In order to investigate the biodiversity of manganese bacteria in polar region, isolation, molecular identification and phylogenetic analysis of manganese bacteria were carried out in the sediments which were collected from Arctic ocean during 2nd Chinese Arctic Scientific Expedition. Twenty one and nineteen species of cultivable strain were isolated from the sediments of both station P11 and S11 respectively according to their distinct morphology on screening plate of manganese medium. Molecular identification and phylogenetic analysis showed that the cultivable manganese bacteria from station P11 were basically composed of γ subgroup of the Proteobacteria branch of the domain Bacteria(γ-Proteobacteria) and Actinobacteria, which accounted for 86% and 14% respectively. The γ-Proteobacteria mainly included Psychrobacter, Shewanella, Acinetobacter and Marinobacter, of which Psychrobacter was the major genus, it accounted for 67% of γ-Proteobacteria in sediments of station P11. The cultivable manganese bacteria from station S11 included α-proteobacteria, γ-Proteobacteria and Flavobacteria of Bacteroides. γ-Proteobacteria included Shewanella, Marinomonas and Alteromonas. The majority of α-Proteobacteria was Sphingomonas. The phylogenetic analysis indicated that bacteria from the sediments of station P11 and S11 had different cultivable manganese bacteria flora. All tested strains had higher resistance to Mn2+, of which Marinomonas sp. S11-S-4 had highest resistance.