This article presents a recent discovery of a dog ( Canis familiaris ) in a hunter -gatherer archaeological site called Huachen, from central Argentine Patagonia. The site is located on the southeastern coast of Colhue Huapi lake. Recently, due to arid climate conditions and desertification processes, the lake is suffering a critical desiccation. Geomorphologically, the site is in a deflation hollow that grows due to strong wind erosion, exposing the archaeological remains. In this context, a skeleton of a male dog between two and three years old was recovered. We present the zooarchaeological, morphological, osteopathological and taphonomic analysis of the remains, as well as the site formation processes. The dog was dated in 300 +/- 30 years BP. This canid presents a particularity: the thoracic and lumbar vertebrae present deviated spinous processes. It is interpreted that this osteopathology is the result of a physical stress induced by weight bearing, possibly due to the use of a pack load. This evidence represents the first case of use of dogs as burden carriers among hunter -gatherers in South America. Huachen has important implications for our understanding of past human mobility. The use of dogs for load transport could have relieved people of the burden of objects, raw materials or other elements that were essential to these groups ' lifestyle. The results allow us to deepen the knowledge about the special bond between people with the dogs and the importance of this domestic animal among Patagonian hunter -gatherer groups with high mobility.