Lannes is a surname. Notable people with the surname include:
Carlos Lannes (born 1979), Argentine cross-country skier
Henriette H. Lannes, central historical figure in the Gurdjieff Foundation
Jean Lannes, duke of Montebello (1769-1809), Marshal of France
Louis Napoléon Lannes (1801–1874), French diplomat and politician
Roberta Lannes (born 1948), American writer