F103 may refer to:
Audi F103, a 1965 internal designation for a series of car models Blas de Lezo (F103), a 2004 Spanish Navy Álvaro de Bazán class frigate Tamiya F103, a 1/10 scale radio controlled Formula One chassis by Tamiya Corporation General Electric F103, a jet engine HMS Lowestoft (F103), a British Royal Navy Rothsay class anti-submarine frigate Republic XF-103 Thunderwarrior, a cancelled fighter aircraft development project