Oberonia carnosa is an epiphytic or lithophytic herb with between four and six fleshy, light green leaves 15–25 mm (0.59–0.98 in) long, 5–8 mm (0.20–0.31 in) wide and curved with their bases overlapping.

The flowering stem has whorls of tiny bracts near its base.

[2][3] Oberonia carnosa was first formally described in 1977 by Bill Lavarack who published the description in the journal Austrobaileya from a specimen he collected from Tozer's Gap on Cape York Peninsula.

[4] The specific epithet (carnosa) is a Latin word meaning "fleshy".

[5] The rockpile fairy orchid grows on trees in sparse scrub in humid places and on trees and boulders in an area of large boulders known as "The Rockpiles".