Abstract: order to obtain highly-efficient denitrifying phosphorous-accumulating bacteria simultaneously removing nitrogen and phosphors, strains were isolated from the samples of Dongting Lake. One effective strain, named as DT4-2, was obtained by culturing with enrichment medium, then isolating with BTB plate, further screening with nitrogen and phosphorus rich medium. The strain was identified as Gemmobacterlanyuensisby morphological characteristics and 16 S rRNA gene sequence analysis. The effect of the strain on removing nitrogen and phosphorus in artificial wastewater was investigated. The results showed that strain DT4-2 could grow best with 2% initial inoculum, and the TP removal rate could reach 96. 7% after 8 h incubation, the TN removal rate was 83. 3% after 60 h in the reaction system. Therefore, the strain DT4-2 has a promising application prospect in eutrophic water treatment.