The fame of the prehistoric sites of Montmaurin is based on the discovery in 1949 of a human mandible of archaic morphology appearance, now curated at the Musée de l’Homme. It comes from a karstic chimney called La Niche. Nearby is the Coupe-Gorge cave, which is larger than the Niche, although it was cut off by a quarry, and in which Louis Méroc undertook excavations with his team from 1946 to 1961. He uncovered some human remains which were later published by Ginette Billy (1982, 1985). 2As part of a multidisciplinary research program initiated in 2018 (Dir. A. Vialet), we examined the ancient collections and resumed the excavation of complex II in two sectors of the cave (2020-2022). Thus, three human remains were added to the five previously discovered. At the same time, a series of U-Th/ESR dates were carried out on the stalagmitic cover and inter-stratified floors and on equid teeth from the lower levels. These analyses made it possible to propose for the first time a chrono-stratigraphic framework for the 7 m high Coupe-Gorge sequence, ranging from 300 ka (complex III) to the Upper Palaeolithic (complex II). Complex III yielded: a fragment of immature mandible (symphysis) and an isolated tooth (RP4) above the stalagmitic floor dated to 200 ka and in the lower levels dated to 300 ka: a right maxilla bearing its P4-P3-C and two isolated teeth (LC sup., RM3). Two teeth (LC sup., RP4) identified in the collections have no stratigraphic provenance. To end, a diaphysis of a left humerus was discovered at the base of complex II during the 2022 excavation campaign. The results of the preliminary study of these fossils will be presented to discuss the development of the Neanderthal lineage in Western Europe during the late Middle Pleistocene.