ABSTRACT The Phacochères site (formerly known as Les Allobroges) is a small ravine belonging to a karst system in northern Algeria. The rescue excavations conducted in 1960s at this site have yielded an exceptionally rich assemblage of vertebrates associated with Aterian stone tools. These faunal fossils collected in sandy clay levels are characteristic of the North African Upper Pleistocene and they represent a remarkable model for understanding the structure of prehistoric mammalian associations, palaeoenvironmental reconstruction and past habitat diversity. Based on biochronological and palaeoenvironmental data, the assemblage is attributed to Marine Isotopic Stage 5 (MIS 5) defined by a forest and grassland ecosystem. This paper reports the results of an analysis of the modifications of this faunal assemblage produced by human and carnivore activity. It suggests that the Aterian occupants of the site preferentially oriented their hunting towards large prey such as buffalo and aurochs and that they were able to compete with other carnivore predators. Nevertheless, the assemblage represents a palimpsest accumulated by different predators, both human and carnivore, that results from events that overlapped with brief human occupations of the site.