A Gram-positive, non-motile, endophytic actinomycete, designated strain YIM 63638T, was isolated from the surface-sterilized roots of Artemisia annua L. The isolate grew optimally with 1–3 % (w/v) NaCl, at pH 6.0–7.0 and at 20–37 °C. Comparative analysis of the 16S rRNA gene sequence showed that the isolate belonged to the genus Pseudonocardia and showed highest sequence similarity with Pseudonocardia oroxyli D10T (98.9 %), Pseudonocardia ailaonensis YIM 45505T (98.3 %) and Pseudonocardia halophobica IMSNU 21327T (98.0 %). Phylogenetic distance from other type strains of species with validly published names within the genus Pseudonocardia was greater than 2.3 %. Strain YIM 63638T had a genomic DNA G+C content of 72.1 mol% and MK-8(H4) as the predominant respiratory quinone. The major fatty acids were iso-C16 : 0 (36.32 %) and 10-methyl-C16 : 0 (19.78 %). On the basis of phenotypic properties and phylogenetic distinctiveness, strain YIM 63638T represents a novel species of the genus Pseudonocardia , for which the name Pseudonocardia xishanensis sp. nov. is proposed. The type strain is YIM 63638T ( = JCM 17906T = KCTC 29005T).