Harry Selby (18 May 1913 – 8 January 1984) was a Scottish politician. A barber by trade, based in Glasgow, he became an active Trotskyist, joining the Revolutionary Socialist League. When this disintegrated, he became a leading figure in the Left Fraction. This group followed a strict policy of entryism in the Labour Party, and although Selby was briefly expelled in the mid-1940s, he was soon readmitted. Following a split in the Left Fraction in 1948, Selby became its leader, and he and his supporters increasingly came to dominate the Glasgow Govan Labour Party.