Commissioned into service in the Italian Regia Marina (Royal Navy) in 1916, she served during World War I, participating in the Adriatic campaign.

[3] On 10 February 1918 Giuseppe Sirtori, Aquila, Ardente, Ardito, Francesco Stocco, and Giovanni Acerbi — and, according to some sources, the motor torpedo boat MAS 18 — steamed to Porto Levante, now a part of Porto Viro, in case they were needed to support an incursion into the harbor at Bakar (known to the Italians as Buccari) by MAS motor torpedo boats.

Sources disagree on whether they remained in port or put to sea to operate in distant support,[4] but in any event their intervention was unnecessary.

[3] While Giovanni Acerbi remained behind to assist Francesco Stocco, the Austro-Hungarians withdrew toward Pola and the Italians resumed operations in support of their own torpedo boats.

On the morning of 4 November, Giuseppe Sirtori, Francesco Stocco, Giovanni Acerbi, and Vincenzo Giordano Orsini got underway from Venice with the battleship Emanuele Filiberto, flagship of Contrammiraglio (Counter Admiral) Guglielmo Rainer, in command of the operation, to take possession of Fiume.

Avoiding a night crossing of the Kvarner Gulf because of the danger posed by minefields there, the other three ships arrived either before 11:30[7] or at 14:00, according to different sources, on 4 November at Fiume, where the Italian population of the city welcomed them.

The force proceeded to Portolago on the island of Leros in the Aegean Sea, from which it operated to protect the Italian Dodecanese from possible acts of hostility on the part of the Kingdom of Greece.

[18] The "Ernesto" convoy, composed of the steamers Aquitania, Castelverde, Ernesto, Nirvo, and Nita and the gunboat Palmaiola,[19] departed Tripoli bound for Naples, Italy, at 07:00 on 27 July 1941[20] with the direct escort of the destroyers Alpino, Folgore, Fuciliere, and Saetta and distant cover provided by the light cruisers Giuseppe Garibaldi and Raimondo Montecuccoli and the destroyers Bersagliere and Granatiere.

[21][22] At 07:00 on 18 August Maddalena Odero was beached at Cala Croce on Lampedusa, but at 13:30 that day five British Royal Air Force Bristol Blenheim bombers of No.

Loaded with ammunition, she exploded,[21][22] sinking the Guardia di Finanza gunboat Maggiore Macchi, which was providing assistance to her.

[22][24] On 5 December 1941 Giuseppe Sirtori was escorting the steamers Tigrai and Vertuno when the British submarine HMS Ultimatum attacked the convoy in the eastern approaches to the Strait of Messina at 37°48′N 016°05′E / 37.800°N 16.083°E / 37.800; 16.083, firing three torpedoes.

[25] On 13 December 1941, Giuseppe Sirtori joined the torpedo boat Cigno and four MAS motor torpedo boats in rescuing 645 survivors of the light cruisers Alberico da Barbiano and Alberto di Giussano, sunk earlier that day by British destroyers in the Battle of Cape Bon off Cape Bon, Tunisia, while attempting to transport fuel from Palermo to Tripoli.

[26] On 5 March 1942 Giuseppe Sirtori, the destroyer Sebenico, and the torpedo boat San Martino escorted the steamers Goggiam and Leonardo Palomba from Corfu to Patras, Greece.

[27] Subsequently, Giuseppe Sirtori underwent modernization which included the removal of two 102-millimetre (4 in)/45 guns and the installation of two depth charge tracks.

[11] On 3 September 1942 Giuseppe Sirtori took in tow the motor ship Monti, torpedoed the previous day 3 nautical miles (5.6 km; 3.5 mi) bearing 090º from Roccella Ionica while operating on the Messina–Crotone route, and beached her near the Fiumara Condoiani at Sant'Ilario dello Ionio, allowing her to be salvaged.

[30] At 10:40 on 16 December 1942 Giuseppe Sirtori left Bizerte, Tunisia, with the torpedo boat Groppo to escort the steamers Campania and Rhea to Naples.

[32] On 27 June 1943, Giuseppe Sirtori, Francesco Stocco, and the auxiliary cruiser Rovigno escorted the steamers Campidoglio, Milano, and Quirinale from Patras, Greece, to Brindisi, Italy, and on 30 June Giuseppe Sirtori and Rovigno escorted the steamers Ezilda Croce and Giorgio Brunner in navigation from Bari, Italy, to Corfu and then on to Patras.

On 13 September, Giuseppe Sirtori and Francesco Stocco were sent to Corfu to support the Italian garrison of the island in defending it from German attacks.