Alinghi 5 is a 90 ft (27 m) (LWL), 90 ft (27 m) beam sloop-rigged catamaran built by Alinghi for the 33rd America's Cup.

Alinghi, or Alinghi Red Bull Racing because of the sports marketing branding by Red Bull, is the syndicate set up by Ernesto Bertarelli, racing under the colors of the Société Nautique de Genève, to challenge for the America's Cup, as well as other competitions. Bertarelli had raced several smaller yachts named Alinghi previously, but 2003 was his first attempt at the America's Cup. Alinghi challenged for and won the 2003 America's Cup in Auckland New Zealand and successfully defended it at the 2007 America's Cup in Valencia, Spain. Alinghi lost the America's Cup to the Golden Gate Yacht Club and their team BMW Oracle Racing in a Deed of Gift match in Valencia, Spain in February 2010.