Henry Tresham RA (c.1751 – 17 June 1814) was an Irish-born British historical painter active in London in the late 18th century.
He spent some time in Rome early in his career, and was professor of painting at the Royal Academy of Arts in London from 1807 to 1809.
Like many other artists in Rome he also acted as a dealer, working with Gavin Hamilton and Thomas Jenkins, and negotiating sales of antiquities to Frederick Hervey and John Campbell.
He also acted as an intermediary between Campbell and the sculptor, Antonio Canova: a pastel by Hugh Douglas Hamilton of Antonio Canova in his studio with Henry Tresham and a plaster model for Cupid and Psyche, showing a work commissioned by Campbell, is in the collection of the Victoria and Albert Museum, London.
His reputation was gained primarily through large-scale history paintings, somewhat similar in style to those of Henry Fuseli.