|northern Argentina, western Paraguay, southern Brazil|
|Linguistic classification:||Mataco–Guaicuru ?
Guaicuruan/Waikurúan languages are often classified as follows:
- Kadiweu (also known as Caduveo, Kadiwéu, Mbayá-Guaycuru, Mbayá, Guaicurú, Waikurú, Ediu-Adig)
- Southern Guaicuruan
- Eastern Guaicuruan
Abipón, Guachí, and Payaguá all are extinct.
Harriet Klein argues against the assumption that Kadiweu is Guaicuruan. Most others accept the inclusion of Kadiweu into the family.
- Toba is spoken in the eastern part of the Chaco and Formosa provinces of Argentina, in southern Paraguay, and in the eastern part of Bolivia; there are approximately 25,000 speakers. The Guaicuruan Toba language here should not be confused with the Mascoy language of the Mascoyan family which is also called Toba (or Toba-Emok, Toba-Maskoy).
- Pilagá, with about 4,000 speakers, is spoken in the northeastern part of Chaco province, and in eastern Formosa, Argentina;
- Mocoví, with about 7,000 speakers, is spoken in Argentina in the northern part of Santa Fe and southern Chaco provinces.
- Abipón, which was spoken in the eastern part of Chaco province, Argentina, is now extinct and was very closely related to the other languages in the southern branch
Jorge Suárez includes Guaicuruan with Charruan in a hypothetical Waikuru-Charrúa stock. Morris Swadesh includes Guaicuruan along with Matacoan, Charruan, and Mascoyan within his Macro-Mapuche stock. Both proposals appear to be obsolete.
- Adelaar, Willem F. H.; & Muysken, Pieter C. (2004). The languages of the Andes. Cambridge language surveys. Cambridge University Press.
- Campbell, Lyle. (1997). American Indian languages: The historical linguistics of Native America. New York: Oxford University Press. ISBN 0-19-509427-1.
- Censabella, Marisa. (1999). Las lenguas indígenas de la Argentina. (pp 60–77). Buenos Aires: Editorial Universitaria de Buenos Aires. ISBN 950-23-0956-1.
- Proel: Familia Guaycuruana