Sam Chai (Thai: สามชัย, pronounced [sǎːm t͡ɕʰāj]) is a district (amphoe) in the northern part of Kalasin province, northeastern Thailand.

Neighboring districts are (from the east clockwise): Kham Muang, Sahatsakhan, and Nong Kung Si of Kalasin Province and Wang Sam Mo of Udon Thani province.

[2] With publication in the Royal Gazette on 24 August, the upgrade became official.

[3] The district is divided into four sub-districts (tambons), which are further subdivided into 46 villages (mubans).

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