William Wyatt Gill (27 December 1828 – 11 November 1896) was an English missionary, active in Australia and the South Pacific region after 1851.
Aaron Buzacott to the Cook Islands met with approval and in June 1851 he was accepted by the London Missionary Society.
On 11 July he was ordained at Spa Fields Chapel and on 15 November he arrived at Hobart Town in the mission ship John Williams where he began his missionary work in Australia.
In 1852-72 Gill worked at Mangaia, Cook Islands, except for five months in 1858 at Rarotonga in charge of the institution for training native teachers and a visit to Sydney in 1862–63.
In 1873 he sailed for England where he read to the Royal Geographical Society his paper 'A Visit to Torres Straits and Mainland of New Guinea'.