Khiri Rat Nikhom (Thai: คีรีรัฐนิคม, pronounced [kʰīː.rīː rát ní(ʔ).kʰōm]) is a district (amphoe) in western Surat Thani province, southern Thailand.

The western part of the district is in the hills of the Phuket mountain range, while to the east the terrain is mostly flat.

The town was first mentioned during the reign of King Mongkut (Rama IV), when it was a minor mueang under Takua Pa and part of the Nakhon Si Thammarat Kingdom.

During the thesaphiban administrative reforms in the 1890s it became a district in Chaiya Province, present day Surat Thani.

[2] Khiri Rat Nikhom is the endpoint of a branch of the southern railway, originally planned to run to Phuket, but construction was halted in 1956.