Prang Ku (Thai: ปรางค์กู่, pronounced [prāːŋ kùː]) is a district (amphoe) in the western part of Sisaket province, northeastern Thailand.

Neighboring districts are (from the north clockwise): Huai Thap Than, Uthumphon Phisai, Wang Hin, and Khukhan of Sisaket Province; Si Narong, Sikhoraphum, and Samrong Thap of Surin province.

The district is named after Prang Samong in Ban Ku.

The district is divided into 10 sub-districts (tambons), which are further subdivided into 141 villages (mubans).

This Sisaket Province location article is a stub.