Sir Alexander Cornewall Duff-Gordon, 3rd Baronet

Sir Alexander Cornewall Duff-Gordon, 3rd Baronet (3 February 1811 – 27 October 1872) was a British civil servant and Baronet of Halkin. He was the husband of Lucie, Lady Duff-Gordon, the English writer on Egypt.

Gordon was born 3 February 1811 the eldest son of Sir William Duff-Gordon, a younger son of the House of Aberdeen and his mother, Caroline, who was a daughter of Sir George Cornewall. He succeeded to his father's title in 1823.

He was for many years a clerk in the Treasury, and acted as private secretary to at least one Chancellor of the Exchequer. He became a senior clerk in the Treasury in 1854, and a Commissioner of Inland Revenue in 1856; he was also Assistant Gentleman Usher of the Privy Chamber to Her Majesty. He died 27 October 1872, his will was probated 6 November, and was valued at less than £15,000. The title passed to his only son Maurice (1849-1896).

Sir Alexander's gravestone is in the churchyard of St Dunstan's Church, Cheam, Surrey. It records "his beloved wife Lucie, only daughter of John and Sarah Austin, who died and was buried in Egypt." There is also an inscription regarding Sir Alexander and Lucie's youngest child, Urania, who was born in November 1858(?) and died 22 September 1877. The inscription is in some places very difficult to read.