Lily of the valley (Convallaria majalis (), sometimes written lily-of-the-valley, is a woodland flowering plant with sweetly scented, pendent, bell-shaped white flowers borne in sprays in spring. It is native throughout the cool temperate Northern Hemisphere in Asia and Europe. Convallaria majalis var. montana, also known as the American lily of the valley, is native to North America.

Due to the concentration of cardiac glycosides (cardenolides), it is highly poisonous if consumed by humans or other animals.

Other names include May bells, Our Lady's tears, and Mary's tears. Its French name, muguet, sometimes appears in the names of perfumes imitating the flower's scent. In pre-modern England, the plant was known as glovewort (as it was a wort used to create a salve for sore hands), or Apollinaris (according to a legend that it was discovered by Apollo).