Jiamao (Chinese: 加茂; pinyin: Jiāmào; also 台 Tái or 塞 Sāi) is a divergent Kra-Dai language or possible language isolate spoken in southern Hainan, China. Jiamao speakers' autonym is tʰai¹.

Jiamao is often classified one of the Hlai languages, which constitute a primary branch of the Kra–Dai language family, but Norquest (2007, 2015) and others note that Jiamao has a non-Hlai substratum.

Graham Thurgood (1992) suggested that Jiamao might have an Austroasiatic substratum. Norquest (2007) identified various lexical items in Jiamao that do not reconstruct to Proto-Hlai and later firmly established it as a non-Hlai language. Hsiu (2018) notes that Jiamao also contains various words borrowed from an unknown, currently extinct Tibeto-Burman branch.

Ostapirat (2026) suggests that Jiamao originated in northern Vietnam before migrating to southern Hainan.

In the 1980s, Jiamao was spoken by 50,000 people in central and south-central Hainan, mostly in Jiamao Township (加茂镇) in Baoting Li and Miao Autonomous County. It shares less than half of its lexicon with the Hlai languages.

In Lingshui Li Autonomous County, Jiamao is spoken in Benhao (本号), Nanping (南平), Wenluo (文罗), Zuguan (祖关), Longguang (隆广), and Tianzi (田仔). In Lingshui County, Jiamao is known as Tái (台), and is also known as Sāi (塞) or Jiāwǒ (加我).^{[citation needed]}

There are four Jiamao dialects, namely Jiamao (加茂), Liugong (六弓), Tianzi (田仔), and Qunying (群英).

Jiamao is spoken in the following villages and townships of southern Hainan.^{[citation needed]}