Thomas de Mowbray, 1st Duke of Norfolk, 1st Earl of Nottingham, 3rd Earl of Norfolk, 6th Baron Mowbray, 7th Baron Segrave, KG, Earl Marshal (22 March 1366 – 22 September 1399) was an English peer.
As a result of his involvement in the power struggles which led up to the fall of Richard II, he was banished and died in exile in Venice.