Nereide was a submarine in the Italian Royal Navy (Italian: Règia Marina) during World War I. She was built 1911–1913 at the navy yard at Venice and was sunk in 1915 by the Austro-Hungarian submarine U-5 under the command of Georg Ritter von Trapp. Nereide's captain, posthumously received the Medaglia d'Oro al Valore Militare for his actions when Nereide was sunk.