Admiral Sir James Hillyar KCB KCH (29 October 1769 – 10 July 1843) was a prominent British Royal Navy officer of the early nineteenth century, who is best known for his service in the frigate HMS Phoebe during the Napoleonic Wars and the War of 1812. While in command of Phoebe, Hillyar was present at the Invasion of Ile de France in 1810, was heavily engaged at the Battle of Tamatave in 1811 and captured the USS Essex off Valparaíso in Chile in 1814.