Sir Thomas Leigh (c. 1504 – 15 November 1571[2]) was an English merchant and Lord Mayor of London in 1558-59.

He was the 2nd great-grandson of Sir Piers Leigh, who was wounded at the Battle of Agincourt in 1415, whose family was a cadet branch of the ancient Leighs, of West Hall, High Legh, Cheshire.

[citation needed] Leigh was raised by Sir Rowland Hill, a City mercer and wool merchant, and later joined Sir Rowland's business, and circa 1535, he married his niece and heir, Alice Barker,[2] daughter of John Barker and Elizabeth née Hill.

One of his daughters, Winifred Leigh, married a later Lord Mayor of London, George Bond.

[8] Another, Katherine Leigh, married Edward Baber MP, Serjeant-at-law and Recorder of Bath.