William Alexander Watson Sheldon (18 January 1907 – 1 November 1999) was an Irish politician and farmer.
He was first elected to Dáil Éireann at the 1943 general election as a Clann na Talmhan Teachta Dála (TD) for the Donegal East constituency.
He was re-elected as an independent TD at the 1944, 1948, 1951, 1954 and 1957 general elections.
He did not contest the 1961 general election as the constituency was reduced from 4 to 3 seats, but was nominated by the Taoiseach, Seán Lemass to the 10th Seanad.
He was re-nominated to the Seanad in 1965 and 1969, and he retired from politics in 1973.
He was also a member of Donegal County Council from 1945 to 1955.