Dezső Földes fenced with the Fővárosi Vívóklub from 1901, before joining Magyar Atlétikai Club (MAC) Budapest. He was trained by the Italian Angelo Toricelli, and competed in both sabre and foil. Földes won his only Hungarian national title, at foil, in 1910, but achieved significant success at international level in the sabre, and was a member of the Hungarian team that won the Olympic title in 1908 and 1912. During his time as an active athlete, he obtained a dentistry diploma at the University of Budapest. In 1912, he emigrated to the United States and opened a sanatorium for poor people in Cleveland. He also opened two treatment centres in the American and the Hungarian sectors. Földes was a member of the jury for the sabre events at the 1932 Los Angeles Olympics.