Hugh Carleton, 1st Viscount Carleton PC (I) SL (11 September 1739 – 25 February 1826), was an Irish judge.
Carleton was born in Cork city, son of Francis Carleton (1713–1791) and Rebecca (d.1791), daughter of Hugh Lawton of Castle Jane and Lake Marsh Co. Cork. His father was a wealthy merchant from a family which settled in Cork in the time of Charles I; he was also a powerful local politician, popularly known as "the King of Cork" for his opulence and respectability. Hugh's maternal grandfather, Hugh Lawton, was a member of the Lawton family of Lawton Hall, Cheshire, who came to Ireland with William III. Hugh Carleton was educated at Kilkenny College, where he became friends with John Scott who stood up for him and protected him. In gratitude, Hugh's father became patron to Scott, the future Earl of Clonmell, and sent both the boys off to Trinity College, Dublin and Middle Temple with equal allowances. Hugh matriculated at Dublin in 1755 and entered Middle Temple in 1758. He was called to the Irish Bar in 1764, becoming King's Counsel in 1768.
With his father's influence Carleton was assured of a seat in the Irish House of Commons: he was elected member for Tuam in 1772, for Philipstown in 1776 and for Naas in 1783. As a politician he was not a success: M.P.s complained he was inaudible, though oddly this fault did not prevent him becoming a highly successful barrister.