Cellulomonas flavigena (Kellerman and McBeth 1912) Bergey et al. 1923 is the type species of the genus Cellulomonas of the actinobacterial family Cellulomonadaceae. Members of the genus Cellulomonas are of special interest for their ability to degrade cellulose and hemicel-lulose, particularly with regard to the use of biomass as an alternative energy source. Here we describe the features of this organism, together with the complete genome sequence, and an-notation. This is the first complete genome sequence of a member of the genus Cellulomonas, and next to the human pathogen Tropheryma whipplei the second complete genome se-quence within the family Cellulomonadaceae. The 4,123,179 bp long single replicon ge-nome with its 3,735 protein-coding and 53 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.