Thomas John Hamilton FitzMaurice, 5th Earl of Orkney (8 August 1803 – 16 May 1877) was a Scottish aristocrat.

His father served as MP for Heytesbury and Denbigh Boroughs.

[2] His paternal grandparents were Mary FitzMaurice, 4th Countess of Orkney and Thomas Fitzmaurice, MP for Calne and Wycombe (who was a younger son of John Petty, 1st Earl of Shelburne).

[3] His great-uncle was British Prime Minister under George III, William Petty-FitzMaurice, 1st Marquess of Lansdowne,[4] who succeeded in securing peace and ending the American War of Independence.

[1] Through his daughter Lady Maria, he was the great-grandfather of Sir Christopher Bullock who was Permanent Under-Secretary for the British Air Ministry.