Strain C17T, a novel strain belonging to the phylum Actinobacteria, was isolated from thermal power plant in Yantai, Shandong Province, China. Cells of strain C17T were Gram-stain-positive, aerobic, pink, non-motile and round with neat edges. Strain C17T was able to grow at 4–42 °C (optimum 28 °C), pH 5.5–9.5 (optimum 7.5) and with 0.0–5.0% NaCl (optimum 1.0%, w/v). Phylogenetically, the strain was a member of the family Gordoniaceae, order Mycobacteriales, class Actinobacteria. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that the closest relative was the type strain of Williamsia faeni JCM 17784T with pair-wise sequence similarity of 98.4%. According to the genome, the DNA G + C content obtained from the draft genome sequence was 64.7%, the main resistant antibiotics were rifamycin, aminoglycoside and glycopeptide, the related gene cluster were clbC,clbB,clbA,vanRI,vanRB,vanRC and vanRD. The average amino acid identity(AAI), average nucleotide identity (ANI) and digital DNA–DNA hybridization(dDDH)values between genome sequences of strain C17T and the type strain Williamsia faeni of the recognized taxa compared were 77.5, 77.9 and 20.7%, respectively. Predominant fatty acids were C16:0(31.7%), C18:1ω9c(26.8%), 10-methyl-C18:0 (16.4%), summed feature comprising C16:1ω7c and/or C16:1ω6c (12.2%) and sum in feature comprising C16:1ω6c and/orC16:1ω7c (10.9%). The major isoprenoid quinone was MK-9 and the diagnostic phospholipids were phosphatidylethanolamine(PE), diphos-phatidylglycerol(DPG) and phosphatidylinositol(PI). Therefore, the combined phenotypic, chemotaxonomic and phylogenetic data indicated that the strain is considered to represent a novel species of the genus Williamsia and the name Williamsia soli sp. nov. is proposed for strain C17T (= KCTC 49567T= MCCC 1K04355T).