A new aerobic, Gram stain-negative, oxidase- and catalase- positive, ovoid or rod-shaped bacterial strain, designated HTCJW17(T), was isolated from a sediment collected from the South China Sea and subjected to a polyphasic taxonomic characterization. The isolate forms small, creamy-white, opaque and circular colonies on agar plates. Growth occurs between 15 and 45 °C, 1-7 % (w/v) NaCl and pH 6-9. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain HTCJW17(T) belongs to the family Kordiimonadaceae of the order Kordiimonadales, with highest sequence similarity to Kordiimonas gwangyangensis GW14-5(T) (91.1 %). The major fatty acids were identified to be summed feature 8 (C18:1 ω7c/ω6c; 56.6 %), C14:0 (8.5 %), C14:0 2-OH (8.4 %), summed feature 3 (C16:1 ω7c/C16:1 ω6c; 6.2 %), and C16:0 (5.2 %). The polar lipids were determined to be phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, six unidentified glycolipids and two unidentified phospholipids. The respiratory quinone was identified as ubiquinone Q-10. The genomic DNA G+C content was determined to be 56.3 mol%. On the basis of genotypic, chemotaxonomic and phenotypic distinctness, we propose a novel genus, Emcibacter gen. nov., with Emcibacter nanhaiensis sp. nov. as the type species. The type strain is HTCJW17(T) (=CGMCC 1.12471(T) = LMG 27419(T) = MCCC 1A06723(T)).