British actor famous for his sitcom roles such as Ralph Dring in Dear John, Michael in Agony and Dennis Dunstable in Please Sir and its spin-off The Fenn Street Gang. He also starred in the 1975 glam rock film Never Too Young to Rock.

Peter John Denyer (20 August 1947 in Dartford – 18 September 2009 in Cheltenham) was an English actor who was perhaps best remembered for playing Dennis Dunstable in London Weekend Television's Please Sir!, and its spin-off series The Fenn Street Gang, taking on the role of a teenager when already into his 20s. He also appeared in the film versions of Please Sir! (1971) and Never Mind the Quality, Feel the Width (1973), and the glam rock film Never Too Young to Rock (1975).