Sir Alexander Milne, 1st Baronet, GCB (10 November 1806-29 December 1896) was a British admiral, the second son of Admiral Sir David Milne.

He entered the Royal Naval College, 8 February 1817. In 1819 he was serving in his father's flagship HMS Leander, on the North American station. Over the next few years he served in HMS Conway, HMS Ramillies, HMS Ganges and HMS Albion. In June 1827 he was an acting Lieutenant in HMS Cadmus on the Brazilian station, and was promoted to substantive Lieutenant on 8 September of that year. Promoted to Commander, 25 November 1830. Commander in HMS Snake , in the West Indies, 1836. Captain, 30 January 1839, commanding HMS Crocodile in North America and the West Indies until November 1841, with a brief spell from November 1840 to March 1841 as Captain of HMS Cleopatra . Flag-captain in HMS Caledonia to his father, the Commander-in-Chief at Plymouth, 27 April 1842 to April 1845. Flag-captain to sir Charles Ogle at Portsmouth, 7 October 1846 to December 1847. A Commissioner of the Admiralty as Fourth Naval Lord , 1847-1852; as Fifth Naval Lord , 1852-1853; again as Fourth Naval Lord, 1853-1857, when he was in charge of British and French transports during the Crimean War; Third Naval Lord, 1857-1859. Rear-Admiral, 20 January 1858. KCB (civil), 20 December 1858. Fourth Naval Lord, April to June 1859; Commander-in-Chief, North America and West Indies, 13 January 1860 to 7 January 1894. KCB (military), 20 February 1864. Vice-Admiral, 13 April 1865. First Naval Lord, July 1866 to December 1868. Commander-in-Chief, Mediterranean, 28 April 1869 to 25 October 1870; Admiral, 1 April 1870. GCB, 24 May 1871. First Naval Lord, November 1872 to September 1876. Created a Baronet, 1 November 1876. Placed on the retired list, 10 November 1876. Admiral of the Fleet, 10 June 1881.

Though never involved in a battle, he was one of the foremost naval administrators of the Victorian era.

Milne Bay , the easternmost inlet of the island of New Guinea, was named after him in 1873.

|- style="text-align: center;" | width="30%" |Preceded by:
Sir Sydney Dacres | width="40%" style="text-align: center;" |First Sea Lord
1872–1876 | width="30%" |Succeeded by:
Sir Hastings Yelverston

Sources include: http://www.pdavis.nl/ShowBiog.php?id=68