Cecil Dudley Seddon (3 July 1902 – 18 April 1978) was an Australian sportsman who represented New South Wales in both cricket and rugby league.

[1] He was one of the New South Wales rugby league team's three-quarters in a representative match against Queensland on 5 June 1921.

[2][3] Seddon made his first-class cricket debut in a 1926/27 Sheffield Shield match against Queensland.

[5] The right-hander made three appearances in New South Wales's winning 1928/29 Sheffield Shield campaign.

[6] His best performance came against Queensland at the Sydney Cricket Ground, where he made a pair of half centuries (80 and 59).