Daniel Oliver, FRS (6 February 1830 – 21 December 1916) was a British botanist. He was Librarian of the Herbarium, Royal Botanic Gardens, Kew from 1860–1890 and Keeper there from 1864–1890, and Professor of Botany at University College, London from 1861–1888.In 1864, while at UCL, he published Lessons in Elementary Biology, based upon material left in manuscript by John Stevens Henslow, and illustrated by Henslow's daughter, Anne Barnard of Cheltenham.