Pritchardia aylmer-robinsonii is a species of palm tree that is endemic to the island of Niʻihau, Hawaii, United States. It inhabits coastal dry forests at an elevation of 70-. P. aylmer-robinsonii reaches a height of 7- and a trunk diameter of 20-. Harold St. John discovered this species in 1949, and the specific epithet refers to Aylmer Francis Robinson, a member of the family that owned the island.[1] P. aylmer-robinsonii has been reintroduced to the Makauwahi Cave Reserve on Kauaʻi, where the species is believed to have previously ranged.[2]