Eugène Vieillard (1819–1896) was a French physician and botanist. Employed as a surgeon with the merchant navy, from 1855 to 1857 he collected plants in Tahiti with gardener-botanist Jean Armand Isidore Pancher. Afterwards, he spent a number of years conducting botanical investigations in New Caledonia, where he was a colleague to naturalist Émile Deplanche. Within this time period, he also collected ferns in New Zealand (1861) and visited the Cape of Good Hope and the island of Réunion. From 1871 to 1895, he was director of the botanical garden in Caen.