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An alkaliphilic actinobacterial strain, designated EGI 80099(T), was isolated from a rhizosphere soil sample of Reaumuria soongorica found in the desert soils of Fukang, Xinjiang, north-west China. Cells of strain EGI 80099(T) were Gram-stain-positive, non-motile, non-endospore-forming cocci. The predominant menaquinones were MK-7, MK-8 and MK-9. The major cellular fatty acids (>10%) were anteiso-C-15:0 and anteiso-C-17:0. Analysis of the cell wall showed the presence of peptidoglycan of the type L-Lys-Gly-L-Glu, variation A4 alpha. Cells of the isolate contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, an unknown phospholipid and an unidentified glycolipid as polar lipids. The genomic DNA G+C content was 63.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain EGI 80099(T) belongs to the genus Nesterenkonia, sharing 95.68-97.37% sequence similarities with the type strains of recognized species within this genus. DNA-DNA hybridization of strain EGI 80099(T) with the type strains of species that showed the highest sequence similarities, Nesterenkonia aethiopica DSM 17733(T) (97.37%), Nesterenkonia flava CAAS 251(T) (97.23%) and Nesterenkonia xinjiangensis YIM 70097(T) (97.02%), gave relatedness values of 8.7-62.2%. Data from DNA-DNA hybridizations and physiological and biochemical tests indicated that strain EGI 80099(T) represents a novel species of the genus Nesterenkonia, for which the name Nesterenkonia rhizosphaerae sp. nov. is proposed. The type strain is EGI 80099(T) (=BCRC 169471=JCM 19129(T)).