Sir William Fraser KCVO (1840 – 16 July 1923) was an Independent Conservative then Reform Party member of parliament in New Zealand.
Fraser was born in India, the son of Captain Hugh Fraser of the 5th Madras Light Cavalry. He received his education at Elizabeth College in Guernsey, Victoria College in Jersey, and the Lycée de St Brieuc in Brittany, France. He came to New Zealand in September 1858 for farming. Together with Alfred Cheetham Strode, he took up Earnscleugh Station on the Earnscleugh River. In 1874, he married Ellen Isabel Strode, the daughter of his business partner, in 1874.
Fraser was a member of the Otago Provincial Council (1867–1870). He was a member of the inaugural Vincent County from 1877 until 1893, the last ten years as chairman. He won the Wakatipu electorate in the 1893 general election, and retired in 1919. He served on the Legislative Council from 1919 to 1923 when he died.
Under Prime Minister William Massey, he was Minister of Public Works (10 July 1912 – 3 April 1920), Minister of Mines (10 July 1912 – 12 August 1915; 4 September 1919 – 27 July 1920), Minister of Industries and Commerce (10 July 1912 – 26 July 1912) and a Member of the Executive Council (without portfolio; 27 July 1920 – 16 July 1923).
He was appointed a Knight Bachelor on 6 February 1918 and, on the occasion of the royal visit by Edward, Prince of Wales to Australia and New Zealand, a Knight Commander of the Royal Victorian Order in 1920.