Liénard is a surname. Notable people with the surname include:
François Liénard de la Mivoye (1782–1862), French-Mauritian naturalist Édouard Liénard (1779–1848), French painter Alfred-Marie Liénard (1869–1958), French physicist and engineer Michel Joseph Napoléon Liénard (1810–1870), sculptor from France Daniel Liénard de Beaujeu, French officer during the Seven Years' War Yann Lienard (born 2003), French footballer Liénard–Wiechert potential describes the electromagnetic effect of a moving electric charge Liénard equation, type of differential equation, after the French physicist Alfred-Marie Liénard