Si Chomphu (, ; , ) is a district (amphoe) of Khon Kaen province, northeastern Thailand.
The district was established as a minor district (king amphoe) on 1 July 1965, when three tambons, Si Suk, Si Chomphu, and Na Chan were split from Chum Phae district. It was upgraded to a full district on 1 March 1969.
Neighboring districts are (from the north clockwise): Si Bun Rueang of Nong Bua Lamphu province; Nong Na Kham, Wiang Kao, and Chum Phae of Khon Kaen Province; and Phu Kradueng of Loei province.
The district is divided into 10 subdistricts (tambons), which are further subdivided into 107 villages (mubans). Si Chomphu is a township (thesaban tambon) and covers parts of tambon Wang Phoem. There are a further 10 tambon administrative organizations (TAO).