Affad 23, situated in upper alluvial deposits related to a former channel of the Nile in the Affad District, Southern Dongola Reach, Sudan, is mainly known through its upper or surface level. The combined data concerning the position of the site, composition of the lithic assemblage, freshness, refittings and dispersion of the artefacts point to a late Middle Palaeolithic workshop used for short periods. It utilized discoid and levallois debitage of Hudi Chert collected from the palaeochannel during the lowwater season. The animal remains suggest opportunistic hunting of medium-sized antelopes, probably mainly kobs living near the site, some dorcas gazelles, occasionally hippopotamus and other big game, as well as small vertebrates, much less visible in the collected samples. A lower level, separated from the surface level by a deposit of some 30 cm, represents an earlier workshop. The easy access to chert in the palaeochannel may also explain the existence of other Paleolithic sites along the channel as workshops.