Together with the "Unicorn", she sailed for the Mediterranean on 13 August to prepare for the landings at Salerno (Operation Avalanche), reaching Malta a week later. Her air group was reinforced at this time by four more Martlets each for 878 and 890 Squadrons. She was assigned to Force H for the operation which was tasked to protect the amphibious force from attack by the Italian Fleet and provide air cover for the carriers supporting the assault force. The Italians made no effort to attack the Allied forces, and the most noteworthy thing that any of her aircraft did was when one of 890 Squadron's Martlets escorted a surrendering Italian aircraft to Sicily. Before the "Illustrious" steamed for Malta she transferred six Seafires to the "Unicorn" to replace some of the latter's aircraft wrecked in deck-landing accidents. Four of these then flew ashore to conduct operations until they rejoined "Illustrious" on 14 September at Malta.