A Gram-positive, moderately halophilic bacterium, referred to as strain Marseille-P3518(T), was isolated from a stool sample with 2% NaCl concentration from a healthy 15-year-old male living in Dielmo, a village in Senegal. Cells are aerobic, rod-shaped and motile and display endospore formation. Strain Marseille-P3518(T) can grow in a medium with 0-20% (w/v) sodium chloride (optimally at 5-7.5% w/v). The major fatty acids were 12-methyl-tetradecanoic acid (45.8%), 13-methyl-tetradecanoic acid (26.9%) and 12-methyl-tridecanoic acid (12.8%). The genome is 4,347,479 bp long with 42.1% G+C content. It contains 4282 protein-coding and 107 RNA genes. Phylogenetic analysis based on 16S rRNA gene sequence comparisons showed that strain Marseille-P3518(T) is a member of the Bacillaceae family and is closely related to Sediminibacillus albus (97.4% gene sequence similarity). Strain Marseille-P3518(T) was clearly differentiated from its phylogenetic neighbors on the basis of phenotypic and genotypic features. Strain Marseille-P3518(T) is, therefore, considered to be a novel representative of the genus Sediminibacillus, for which the name Sediminibacillus massiliensis sp. nov. is proposed, and the type strain is Marseille-P3518(T) (CSUR P3518T, DSM69894).