Chimariko is an extinct language isolate formerly spoken in northern Trinity County, California, by the inhabitants of several independent communities. While the total area claimed by these communities was remarkably small, Golla (2011:87–89) believes there is evidence that three local dialects were recognized: Trinity River Chimariko, spoken along the Trinity River from the mouth of South Fork at Salyer as far upstream as Big Bar, with a principal village at Burnt Ranch; South Fork Chimariko, spoken around the junction of South Fork and Hayfork Creek, with a principal village at Hyampom; and New River Chimariko, spoken along New River on the southern slopes of the Trinity Alps, with a principal village at Denny.

Proposals linking Chimariko to other languages in various versions of the hypothetical Hokan family have been advanced. Roland Dixon suggested a relationship between Chimariko and the Shastan and Palaihnihan families. Edward Sapir's famous 1929 classification grouped Chimariko with Shastan, Palaihnihan, Pomoan, and the Karuk and Yana languages in a Hokan sub-grouping known as Northern Hokan. A Kahi family consisting of Chimariko, Shastan, Palaihnihan, and Karuk has been suggested (appearing also within Sapir's 1929 Northern Hokan). Most specialists currently find these relationships to be undemonstrated, and consider Chimariko to remain best considered an isolate.

Stephen Powers collected the first word list from Chimariko speakers in 1875 (Golla, 2011, p. 89). Soon after, Jeremiah Curtin documented a substantial amount of information (p. 89). Roland Dixon began work on the Chimariko language in the early 1900s, when there were few remaining speakers. Dixon worked with two: Mrs. Dyer and a man who was named Friday. While doing work with nearby Hupa, Edward Sapir collected data and also commented on the earlier Dixon work (Golla, 2011, p. 89). Later, extensive documentation on the language was carried out by J.P. Harrington, who worked with Sally Noble, the last speaker of the language. None of this work has been published, but slides of all of Harrington's work can be viewed on the Smithsonian Institution's website. Harrington's assistant John Paul Marr also made recordings of the language with speaker Martha Zigler. George Grekoff collected previous works of linguistics intending to write a grammar, but died before it was completed (Golla, 2011, p. 89). The last Chimariko speaker was Martha Ziegler who died in the 1950s (Golla, 2011, p. 89). According to Golla, bilingual Hupa-Chimariko speakers native to the South Fork of the Trinity River, Burnt Ranch and New Rivers areas, organized as the Tsnungwe Tribe (from Hupa cʰe:niŋxʷe: 'Ironside Mountain people') and are seeking federal acknowledgement, but emphasize Hupa for purposes of cultural revitalization". There are no programs available to either teach or revitalize Chimariko from its current status of extinct (p. 89).

The consonant inventory of Chimariko is:

The vowel inventory of Chimariko is: i, e, a, o, u.

Chimariko shares syllabic similarities with other languages in Northern California. The most common syllable structures for Chimariko are CV and CVC, with the largest possible structures being CCVC or CVCC.

Noun incorporation is present in Chimariko. The verbs have prefixes, suffixes and a circumfix.

Verb templates: