Det Udom (Thai: เดชอุดม) is a district (amphoe) in the southern part of Ubon Ratchathani province, in northeastern Thailand.

Neighboring districts are (from the northwest clockwise) Samrong, Warin Chamrap, Na Yia, Phibun Mangsahan, Buntharik, Na Chaluai, Nam Yuen, Nam Khun, Thung Si Udom of Ubon Ratchathani Province, and Benchalak of Sisaket province The district is divided into 16 sub-districts (tambons), which are further subdivided into 229 villages (mubans).

There are also three townships (thesaban tambons): Na Suang and Bua Ngam each cover parts of the same-named tambon, and Kut Prathai covers tambon Kut Prathai.

Missing numbers are tambons which now form Districts Na Yia and Thung Si Udom.

This Ubon Ratchathani Province location article is a stub.