Zamostje 2 is an open-air site, discovered in a bog in central Russia and excavated by V. Lozovski from 1989. It is basically a border of an habitation and fishing zone, partially with a waste area. This deposit is characterised by a successive stratigraphy of Late Mesolithic to Neolithic, linked to an assemblage unusually preserved because of humid conditions. This study aims to establish the “chaine opreratoire” of butchery in the Late Mesolithic (7900 ± 180 BP and 7050 ± 60 BP) of elk, which is the most represented species. A quantitative analysis of human traces was performed in order to identify the different phases of acquisition, processing, and consumption of resources provided by the elk. This research showed standardized butchery activity with the highlighting of a primary phase (skinning, removal of tendons, decapitation, and carcass reduction) performed on the kill site and a secondary phase (disarticulation, filleting, and extraction of the marrow...) in the base camp. This work also illustrates the intensity of fracturing for marrow recovery, especially for anatomical parts with a low proportion of marrow (phalanges). The specificity of this reduction processes is related to environmental and economic constraints in the context of the Mesolithic in Eastern Europe.