Thoeng (Thai: เทิง; IPA: [tʰɤ̄ːŋ]) is a district (amphoe) in the eastern part of Chiang Rai province, northern Thailand.

Neighboring districts are (from the southwest clockwise) Pa Daet, Mueang Chiang Rai, Wiang Chai, Phaya Mengrai, Khun Tan, and Wiang Kaen of Chiang Rai Province.

The conspicuous 1,174 m high Doi Ian rises 12 km to the east and 823 m high Doi Kham rises four km south of the town between Thoeng and Chiang Kham.

[1] The Ing River, with its source in the Phi Pan Nam Range (Doi Luang in Mae Chai district, Phayao Province) flows through the plain area of Thoeng.

Missing numbers belong to tambons which now form Khun Tan District.