The Zakhchin (Mongolian: Захчин) is a subgroup of the Oirats residing in Khovd Province, Mongolia.

They originally spoke the Zakhchin dialect of the Oirat language, but actually pure Oirat language is used by elder generations, younger generations use a dialect being under a strong Khalkha influence.

The Zakhchins conquered by the Manchus of the Qing dynasty in 1754 and controlled by Zasagt Khan aimag's Tsevdenjav gün, then moved to Zereg and Shar Khulsan.

One Banner with 4(+1) sums were designated for them and noble Maamad (Mamuud) zaisan became the chieftain but Mamuud killed by Zungharian king Amarsanaa later and the Zakhchins revolted together with Amursana against the Qing.

During the Bogd Khanate of Mongolia, Zakhchin was subject to Dörbet Ünen Zorigt Khan aimag.