They are spoken in mountainous areas of southern China, including Guizhou, Hunan, Yunnan, Sichuan, Guangxi, Guangdong and Hubei provinces; the speakers of these languages are predominantly "hill people", in contrast to the neighboring Han Chinese, who have settled the more fertile river valleys.

The Hmongic languages appear to have kept the large set of initial consonants featured in the protolanguage but greatly reduced the distinctions in the syllable finals, in particular losing all glides and stop codas.

The current consensus among Western linguists is that they constitute a family of their own, the lexical and typological similarities among Hmong–Mien and Sinitic languages being attributed to contact-induced influence.

In Mandarin, despite the fact that it was once a derogatory term, the word Miao (Chinese: 苗; the tone varies according to the Sinitic dialect) is now commonly used by members of all nationalities to refer to the language and the ethnolinguistic group.

It includes peoples speaking Mien, Kra–Dai, Yi, and Miao languages, the latter called Bùnǔ rather than Miáo when spoken by Yao.

[11] Besides their tonality and lack of adpositions, another striking feature is the abundance of numeral classifiers and their use where other languages use definite articles or demonstratives to modify nouns.