Vesper or Vesper Martini is a cocktail made with three shots of dry gin, one shot of vodka, and half a shot of Kina Lillet (nowadays known as Lillet Blanc), a dry French vermouth. It was invented by Ian Fleming, when it was mentioned in his first James Bond novel, Casino Royale, published in 1953.

In the novel, agent 007 orders it in a deep champagne goblet, well-shaken with ice, and garnished with a large slice of lemon peel. The cocktail is named after a female agent Vesper Lynd, who turned out to be a double agent at the end of the novel.