The Puelche (Mapudungun: pwelche, "people of the east") were indigenous peoples living east of the Andes Mountains in Chile and Southwest Argentina in the 18th century. They spoke the Puelche language. The name "Puelche" was not native, but was given to them by the Mapuche. They were annihilated by plagues and epidemics in the late 18th century, with survivors merging into other groups such as the Mapuche, Het, and Tehuelche.
The Puelche are commemorated in the scientific name of a species of lizard, Liolaemus puelche, which is endemic to Mendoza Province, Argentina.