Omkoi (Thai: อมก๋อย, pronounced [ʔōm.kɔ̌j]) is the southwesternmost district (amphoe) of Chiang Mai province in northern Thailand.

Neighboring districts are (from the north clockwise) Hot and Doi Tao of Chiang Mai Province, Sam Ngao, Mae Ramat, and Tha Song Yang of Tak province and Sop Moei of Mae Hong Son province.

The minor district (king amphoe) was established on 19 April 1929 as a subordinate of Hot district, consisting of the three sub-districts Omkoi, Yang Piang, and Mae Tuen.

[2] The district is divided into six sub-districts (tambon), which are further subdivided into 95 villages (muban).

This Chiang Mai province location article is a stub.