South American Indians of the Gran Chaco, who speak an independent language and live mostly between the Bermejo and Pilcomayo rivers in northeastern Argentina. Some live in Bolivia. The Wichí are the largest and most economically important group of the Chaco Indians. They combine limited agriculture with fishing, hunting, and gathering of wild foods.

When the Wichí were first contacted by Europeans they responded peacefully but resisted European attempts at Christianization and colonization. Many were massacred, placed on reservations, or incorporated into government colonies. Today, the Wichí are being assimilated into the mestizo (mixed-blood) population of the Chaco. At the turn of the 21st century their population was estimated at some 40,000 individuals. Many work as lumberjacks or migrate annually to employment on the sugar plantations of Jujuy and Salta.