[2][3][4] As currently known, it is endemic to Kanchanaburi Province in western Thailand,[2][4] on the eastern slopes of the Bilauktaung Range.

Most individuals have light yellow markings running from beneath the eye along the flank to the groin.

[1] Ansonia pilokensis is only known from its type locality, Pilok Subdistrict in the Thong Pha Phum National Park, at 942 m (3,091 ft) above sea level.

At the type locality, Ansonia pilokensis were primarily found on banks along small mountain streams at night.

However, one specimen was found during the day in leaf litter along a path five meters from a stream.