La Croix de Bagneux is an open-air prehistoric site located in Mareuil-sur-Cher, Loir-et-Cher, in the Centre-Val de Loire region, France.

It is an exceptional deposit for the study of several cultures of the Early Upper Paleolithic and early Magdalenian, hitherto poorly represented in the region. On the one hand, it was regularly occupied by temporary hunter-gatherer camps for a very long time, presumably for the abundant flint resources nearby and, supposedly, for the abundance of food resources. On the other hand, the nature of the soil has generally allowed good conservation of the remains of these successive occupations, conditions that are generally known only in caves or under shelter.