Phu Sing is a district (amphoe) in the southwestern part of Sisaket Province, northeastern Thailand. The minor district (king amphoe) was created on 1 April 1991, when the six tambons Khok Tan, Huai Ta Mon, Huai Tuekchu, Lalom, Takhian Ram, and Dong Rak were split off from Khunkhan District. It was upgraded to a full district on 8 September 1995.
The district is bounded in the south by the Dangrek Range. Neighbouring districts are (from the west clockwise): Buachet of Surin Province, Khukhan, and Khun Han of Sisaket Province, and Oddar Meancheay of Cambodia.
The district is divided into seven sub-districts (tambons), which are further subdivided into 85 villages (mubans). There are no municipal (thesaban) areas, and seven tambon administrative organizations (TAO).

Source: https://en.wikipedia.org/wiki/Phu_Sing_District