William Murdoch Adamson (12 April 1881 – 25 October 1945) was a British Labour politician, and the son of his namesake, the Labour MP and Leader of the Labour Party, William Adamson.
He was a National Officer of the Transport and General Workers' Union. In 1902 he married Jennie Johnston, later Member of Parliament for Dartford and Bexley.
He was Labour Member of Parliament (MP) for Cannock, in Staffordshire from 1922–1931 and from 1935-1945. He served in government as a Lord Commissioner of HM Treasury from 1941-1944.