Achille Cantoni (1835 – 3 November 1867) was an Italian war volunteer who fought in the Second and Third Italian Wars of Independence. He is credited with saving the life of Giuseppe Garibaldi, an Italian general and central figure of the Risorgimento, during a battle in the town of Velletri in 1849. He died at the Battle of Mentana on November 3, 1867. After his death, Giuseppe Garibaldi wrote a novel entitled "Cantoni il volontario" in his honor.