This paper deals with the process of faunal recomposition that occurred during the Late Glacial in the Jura and northern French Alps, based on a critical analysis of the faunal spectra and radiocarbon dates. More than fifty AMS radiocarbon dates of different faunal species allow a chronology of the faunal transition to be suggested. A first phase has been identified for the second part of the Older Dryas with a decrease in large-sized taxa (woolly rhinoceros, mammoth and carnivores) which were an important component in previous ecosystems and were still represented in the faunal assemblages dated to the beginning of the Late Glacial. During the 13th millennium cal BC three large cervid species (red deer, elk, reindeer) were present (at least seasonally) in the environment. The retreat of reindeer from eastern France, dated to 12300- 12100 cal BC with no reappearance in France during the Last Cold Oscillation (YD) is one of the most striking pieces of evidence of the acceleration of an irreversible process. Increased warming around 12700 cal BC, interspecific competition and behaviour of the Azilian groups with a change in their subsistence strategy may have been determining factors. Red deer populations expanded significantly at that time in an open environment and became the main large game hunted by Azilian groups. The decrease of the frequencies of Horse, together with alpine and rocky taxa (mountain hare, marmot, ibex) is also a distinctive pattern of the process at the end of the Late Glacial.