Jean François Marie Le Gonidec de Kerdaniel (Breton: Yann-Frañsez ar Gonideg) (4 September 1775 – 12 October 1838) was a Breton grammarian who codified the Breton language.
He played an important role in the history of his native language by initiating a reform of its orthography, producing an orderly grammar and making the first Breton translation of the New Testament.
He is sometimes called "Reizher ar brezhoneg" (Restorer of the Breton language).