Robert Lloyd Praeger was an Irish naturalist, writer and librarian.
Praeger worked in the National Library of Ireland in Dublin from 1893 to 1923. He co-founded and edited the Irish Naturalist, and wrote papers on the flora and other aspect of the natural history of Ireland. He organised the Lambay Survey in 1905/06 and, from 1909 to 1915, the wider Clare Island Survey. He was an engineer by qualification, a librarian by profession and a naturalist by inclination.