Admiral Norwich Duff FRSE (15 August 1792 – 21 April 1862[1]) was a Royal Navy officer.

The son of Captain George Duff RN, and Sophia Dirom, he was born at 9 South Castle Street, Edinburgh.

He entered the Royal Navy in July 1805, just before his 13th birthday, serving aboard his father's ship Mars as a midshipman.

The couple's eldest daughter, (Helen) Sophia Duff 1834–1930, married Boscawen Trevor Griffith (whose name later changed to Griffith-Boscawen) as a result of which Norwich became the maternal grandfather of Arthur Sackville Trevor Griffith-Boscawen 1865–1946, a prominent British Conservative politician during the early decades of the twentieth century.

There is a portrait of him by Sir Henry Raeburn, and a metal plaque commemorates him in Bath Abbey.