After doing a review of the main biological, archaeological and ethnographic data related to the species Cavia porcellus in the Andes, we focus in the study of 112 naturally mummified guinea pigs found buried underneath the floor of four residences at El Yaral, a prehispanic village located in the Osmore drainage of the extreme south of Peru. This finding has documented ritual practices involving the sacrifice of these animals. Evidence concerning pre and post-Conquest guinea pig use is presented. These data indicate continuity through time in ritual practices and beliefs related to this animal up to the present day.