William Thomas Ely (7 June 1869 – 19 April 1957) was an Australian politician. He was a Labor Party member of the New South Wales Legislative Assembly from 1920 to 1922 and 1925 to 1932, representing the electorates of Parramatta (1920–22, 1925–27) and Granville (1927–1932). He was Minister for Health during the second Lang government from 1931 until 1932. Ely retired from politics after his 1935 loss, and subsequently became a poultry farmer. He died at Bondi in 1957.