Ilyobacter polytropus Stieb and Schink 1984 is the type species of the genus Ilyobacter, which belongs to the fusobacterial family Fusobacteriaceae. The species is of interest because its members are able to ferment quite a number of sugars and organic acids. I. polytropus has a broad versatility in using various fermentation pathways. Also, its members do not degrade poly-β-hydroxybutyrate but only the monomeric 3-hydroxybutyrate. This is the first completed genome sequence of a member of the genus Ilyobacter and the second sequence from the family Fusobacteriaceae. The 3,132,314 bp long genome with its 2,934 protein-coding and 108 RNA genes consists of two chromosomes (2 and 1 Mbp long) and one plasmid, and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.