Sava (pennant number P-802) was a Flutto-class submarine in service with the Yugoslav Navy (Serbo-Croatian: Jugoslavenska ratna mornarica – JRM).

Built by Cantieri Riuniti dell'Adriatico in Monfalcone during the Second World War, Sava was laid down and completed as Nautilo for service with the Italian Regia Marina (Royal Navy).

Sava was laid down on 3 January 1942 as Nautilo, the eighth boat of the Type 1 Flutto-class submarines that were being built for the Regia Marina (Royal Navy) by Cantieri Riuniti dell'Adriatico, Monfalcone.

After the end of the war, the boat was raised by the Yugoslav Navy (Serbo-Croatian: Jugoslavenska ratna mornarica – JRM) and moved to the Uljanik Shipyard where she underwent repairs which lasted from 1947 to 1949.

[1] The boat was commissioned in 1949 as Sava (pennant number P-802),[2] and with the Mališan (P-901) and Tara (P-801), formed the basis of the new Yugoslav submarine fleet.