The site of Kostënki 21 (also known as Gmelin or Gmelinskaia) is located on the very edge of the Don River at Kostënki (Voronezh Oblast, Russia). The main archaeological horizon, layer III, is dated to c. 23,000-21,000 14 C BP (c. 27,500-24,500 cal BP) and contained six concentrations of archaeological material, mostly interpreted as the remains of dwelling structures. A substantial Gravettian lithic assemblage was found. The site has traditionally been seen as without parallels within the Gravettian chronocultural framework of Eastern Europe. It has long been noted that clear differences in the lithic typology and faunal assemblages of the six concentrations can be used to separate them into two groups, but this has previously been attributed to differences in the activities carried out in the two areas. In this paper, we argue that the two parts of the site were created at different times and that one part of the site can potentially be grouped with several other sites in Russia and Ukraine on lithic technotypological grounds. The degree of patination of the flint artefacts found at the site provides support for our interpretation.