Nestor Léon Marchand (15 April 1833 – 16 April 1911) was a French medical doctor, pharmacist, and botanist.
He is known for his studies of the flowering plant family Anacardiaceae.
He studied in Tours and Paris, subsequently earning a bachelor of science degree (1860), a doctorate in medicine (1861), a first-class license in pharmacy (1864) and a doctorate in natural sciences (1867).
He later became a professor of botanical cryptogamy at the École supérieure de pharmacie in Paris.