Sir Harold Seddon (6 March 1881 – 25 February 1958) was an Australian politician who served as a member of the Legislative Council of Western Australia from 1922 to 1954.
He emigrated to Australia in 1901, finding employment on the Eastern Goldfields as an electrical engineer with Western Australian Government Railways.
Seddon became prominent in the Amalgamated Engineering Union, and also served on the Southern Cross Municipal Council.
He stood as the party's candidate in the seat of Kalgoorlie at the 1917 state election, but was defeated by the sitting member, Labor's Albert Green.
[1] In November 1946, following the death of the President of the Legislative Council, James Cornell, Seddon was elected in his place.