Nils Johan Andersson (20 February 1821 Gärdserum, Småland, Sweden - 27 March 1880 Stockholm), was a Swedish botanist and traveller. He studied at Uppsala University between 1840-45 obtaining a DSc. On 30 September 1851 he accompanied the Swedish expedition as botanist aboard the frigate "HMS Eugenie", sailing from Karlskrona under the command of Captain Christian Adolf Virgin (1797-1870), on the first Swedish circumnavigation, calling at Honolulu, Tahiti, San Francisco, Sydney and Manila, various South American ports, the Galapagos, Hong Kong and Singapore. On this voyage he collected at the Cape of Good Hope in April 1853. Returning to Sweden, he was appointed Professor of Botany at Lund University. He was also director of the Botanical Department of the Swedish Museum of Natural History and the Hortus Bergianus in Stockholm. His special interests were Salix, Cyperaceae and Gramineae and he published numerous papers on the systematics and morphology of these taxa.