Admiral Sir William Edmonstone, 4th Baronet CB, DL (29 January 1810 – 18 February 1888), also 14th of Duntreath, was a Scottish naval commander, courtier and Conservative politician.
Born at Hampton, Edmonstone was Member of Parliament for Stirlingshire from 1874 to 1880, and an Aide-de-Camp to Queen Victoria. He was an admiral in the Royal Navy, and was appointed a Companion of the Order of the Bath (CB).
Edmonstone married at Zakynthos, Greece, on 13 July 1841, Mary Elizabeth Parsons (Newburn, Fife, 21 June 1823 – Cramond House, Midlothian, 11 August 1902), daughter of Lieutenant-Colonel Parsons, CMG, who was British Resident on the island of Zante, at a time when the Ionian Islands were a British Protectorate. Mary Elizabeth and Sir William in all had eleven children, nine of whom survived into adulthood:
Sir William Edmonstone died at Edinburgh on 18 February 1888, and was succeeded in the baronetcy by his only surviving son, Archibald Edmonstone. Lady Edmonstone died at Cramond House, Midlothian on 11 August 1902.