The Battle of Cape Passaro, also known as Battle of Avola or Battle of Syracuse, was a major naval battle fought on 11 August 1718 between a fleet of the British Royal Navy under Admiral Sir George Byng and a fleet of the Spanish Navy under Rear-Admiral Antonio de Gaztañeta. It was fought off Cape Passaro, in the southern tip of the island of Sicily of which Spain had occupied. Spain and Britain were at peace, but Britain was already committed to supporting the ambitions of the Emperor Charles VI in southern Italy.

Admiral of the Fleet George Byng, 1st Viscount Torrington,, of Southill Park in Bedfordshire, was a Royal Navy officer and statesman. While still a lieutenant, he delivered a letter from various captains to Prince William of Orange, who had just landed at Torbay, assuring the Prince of the captains' support; the Prince gave Byng a response which ultimately led to the Royal Navy switching allegiance to the Prince and the Glorious Revolution of November 1688.