Thung Si Udom (Thai: ทุ่งศรีอุดม) is a district (amphoe) in the southwestern part of Ubon Ratchathani province, northeastern Thailand.

[1] The inclusion of tambon Thung Thoeng into the new district was undone on 1 June 1993.

[3] The district is divided into five sub-districts (tambon), which are further subdivided into 52 villages (muban).

There are no municipal (thesaban) areas, and five tambon administrative organizations (TAO).

Geocode 1 was assigned to Thung Thoeng, which was returned to Det Udom district This Ubon Ratchathani Province location article is a stub.