Nong Bun Mak (, ) is a district (amphoe) of Nakhon Ratchasima province, northeastern Thailand.
Nong Bunnak was created as a minor district (king amphoe) on 1 July 1983 by separating the three tambons, Nong Bunnak, Saraphi, and Thai Charoen, from Chok Chai district. It was upgraded to a full district on 25 May 1989. In 2003 the district was renamed from Nong Bunnak to Nong Bun Mak.
Neighbouring districts are (from the east clockwise): Nong Ki of Buriram province; Khon Buri, Chok Chai, and Chakkarat of Nakhon Ratchasima Province.
The district is divided into nine subdistricts (tambons), which are further subdivided into 104 villages (mubans). There are no municipal (thesaban) areas, and nine tambon administrative organisations (TAO).