A novel strain, designated NS18(T), was isolated from sediment sampled at Taihu Lake, PR China. Cells of the isolate were spherical, aerobic, non-motile, Gram-stain-positive and non-endospore-forming. Phylogenetic analysis based on 165 rRNA gene sequences revealed that strain NS18(T) clustered in a Glade of the genus Agrococcus. Its closest phylogenetic neighbour was Agrococcus lahaulensis DSM 17612(T) with 98.2% 165 rRNA, gene sequence similarity. The complete genome of NS18(T) was 2736037 bp and its genomic DNA G+C content was 72.8 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain NS18(T) and A. lahaulensis DSM 17612(T) based on their whole genomes were 85.1 and 28.7%. respectively. The major fatty acids were anteiso-C-17:0 and anteiso-C-15:0. The predominant menaquinones were MK11 and MK12. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol and two unidentified lipids. The components of the peptidoglycan were Ala, Gly, Asp, Thr and DAB. The whole-cell sugars contained rhamnose, ribose, xylose and glucose. According to the results of phenotypic, chemotaxonomic and phylogenetic analyses, strain NS18(T) (=NBRC 113859(T)=MCCC 1K03759(T)) represents a novel species, for which the name Agrococcus sediminis sp. nov is proposed.