Khlong Saeng (Thai: คลองแสง) is a wildlife sanctuary in southern Thailand, in western Surat Thani Province.

Most lowland areas in the Khlong Saeng valley were flooded with the construction of the dam and the creation of Cheow Lan Reservoir.

This now flooded area was the only site in Thailand where Storm's stork (Ciconia stormi) was confirmed to breed in 1986.

In 2019, cameras were installed in the sanctuary to take pictures of endangered and protected animals in a 750,000-rai area north of the Ratchaprapha Dam.

Photos captured rare animals such as clouded leopards and Asian golden cats.