A novel actinomycete strain, designated YIM 63587(T), was isolated from surface-sterilized roots of Artemisia annua L. collected from Yunnan province, south-west China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 63587(T) was affiliated to the genus Pseudonocardia. 16S rRNA gene sequence similarities between strain YIM 63587(T) and type strains of species of the genus Pseudonocardia were 96.6-93.8 %. The diagnostic cell-wall diamino acid in the peptidoglycan layer of strain YIM 63587(T) was meso-diaminopimelic acid and the whole-cell sugars were arabinose, galactose, mannose and ribose. The predominant menaquinone was MK-8(H(4)) (97.7 %). The phospholipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, phosphatidylinositol mannosides, phosphatidylinositol and an unknown phospholipid. The major cellular fatty acids (>5 %) were iso-C(16 : 0) (44.7 %), iso-C(14 : 0) (10.3 %), iso-C(16 : 1) H (9.8 %) and iso-C(15 : 0) (7.7 %). The G+C content of the genomic DNA was 68.2 mol%. On the basis of phylogenetic, physiological and chemotaxonomic data, strain YIM 63587(T) represents a novel species of the genus Pseudonocardia, for which the name Pseudonocardia artemisiae sp. nov. is proposed. The type strain is YIM 63587(T) ( = DSM 45313(T) = CCTCC AA 208081(T)).