Admiral of the Fleet Sir Algernon Usborne Willis (17 May 1889 – 12 April 1976) was a Royal Navy officer. He served in the First World War and saw action at the Battle of Jutland in May 1916. He also served in the Second World War as Commander-in-Chief, South Atlantic in which capacity he led actions against German and Japanese raiding ships. He continued his war service as Flag Officer commanding 3rd Battle Squadron and Second in command of the Eastern Fleet and then as Flag Officer commanding Force H, the force which covered North African Operations, the Allied invasion of Sicily in July 1943 and then the Allied invasion of Italy in September 1943. He spent the final years of the war as Commander-in-Chief, Levant, in which capacity he conducted naval operations in support of the Dodecanese Campaign, and then as Second Sea Lord, in which capacity he arranged the manpower for the campaign in the Pacific Ocean against the Imperial Japanese Navy. After the war he served as Commander-in-Chief, Mediterranean Fleet, in which role he was faced with unrest in Mandatory Palestine, before he became Commander-in-Chief, Portsmouth.