Seamus Frederick Mallon (; 17 August 1936 – 24 January 2020) was an Irish Gaelic footballer and politician. He was deputy First Minister of Northern Ireland from 1998 to 2001 and Deputy Leader of the Social Democratic and Labour Party from 1979 to 2001. He also was a Seanad Éireann in 1986 and MP from 1986 to 2005.