A novel Gram-reaction-positive, non-motile and facultatively anaerobic bacterium, designated strain S01T, was isolated from a nutrient agar plate kept on a laboratory clean bench at Guangdong Institute of Microbiology, PR China, which was contaminated from an unknown source. Strain S01T was found to be catalase-positive and oxidase-negative. Similarity searches revealed that the strain shared the highest 16S rRNA gene similarity with Corynebacterium humireducens MFC-5T (95.9 %). However, phylogenetic analysis based on the 16S rRNA gene sequences showed that strain S01T was closely related to Corynebacteriumdoosanense JCM 17317T (94.8 %) and Corynebacterium maris JCM 17018T (94.8 %). The major fatty acids were C18:1ω9c, C16:0, 10-methyl C18:0 and C18:0. The respiratory quinones predominantly consisted of MK-8(H2), with small amounts of MK-8 and MK-9(H2). Polar lipids contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, an unidentified aminolipid, two unidentified glycolipids and two unidentified lipids. Mycolic acids were present. The cell-wall peptidoglycan contained meso-diaminopimelic acid and the major cell-wall sugars were galactose, arabinose and glucose. The genomic DNA G+C content of strain S01T was 70.7±0.1 mol%. The results of phenotypic, phylogenetic and chemotaxonomic analyses indicated that strain S01T represents a novel species of the genus Corynebacterium, for which the name Corynebacterium guangdongense sp. nov. is proposed. The type strain is S01T (=GDMCC 1.1022T=CCTCC AB 2015423T=KCTC 39608T).