Tai Yo, also known as Tai Mène and Nyaw, is a Tai language of Southeast Asia. It is closely related to Tai Pao of Vietnam, where it may have originated. It was once written in a unique script, the , but that is no longer in use. The language is known regionally in Laos and Thailand as Tai Mène and Tai Nyaw and, in Vietnam as Tai Do and Tai Quy Chau. Superficially, Tai Yo appears to be a Southwestern Tai language but this is only because of centuries of language contact and it is properly classified with the Northern Tai languages. The Nyaw/Nyo spoken in central Thailand and western Cambodia is a dialect of Lao and not the same as Tai Yo.