For the modern Romance languages spoken in Switzerland and North-Eastern Italy, see Rhaetian languages.

Raetian was a language spoken in ancient times by the tribes of the Raetians in the areas around the Alps (in Switzerland, Austria, North-Eastern Italy and Southern Germany). The most common theory is that it was related to the Etruscan language.

Raetian became extinct by the 3rd century, after the speakers were assimilated and adopted Latin (in south) and German (in north). Many inscriptions are known, but most of them are short votive texts, written with the Etruscan alphabet.

An early theory said that Raetian was an intermediary language between Celtic languages (in East) and Illyrian language (in the west), however evidence showed some linguistic afinities with Etruscan, a Pre-Indo-European language which used to be spoken to the south, in Italy.

Raetian and Etruscan share some word endings and even some words were identified as being cognate with Etruscan (but they could be simply borrowings). This theory is supported by the Ancient Roman writers, who considered the Rhaetians a subgroup of the Etruscan.